diff --git a/src/GCodes/GCodeBuffer/ExpressionParser.h b/src/GCodes/GCodeBuffer/ExpressionParser.h
index 38de851733..30e4148cea 100644
--- a/src/GCodes/GCodeBuffer/ExpressionParser.h
+++ b/src/GCodes/GCodeBuffer/ExpressionParser.h
@@ -61,7 +61,7 @@ class ExpressionParser
 	void ParseDriverIdArray(DriverId arr[], size_t& length) THROWS(GCodeException);
 
 	void CheckForExtraCharacters() THROWS(GCodeException);
-	const char *GetEndptr() const noexcept { return currentp; }
+	const char *_ecv_array GetEndptr() const noexcept { return currentp; }
 
 private:
 	[[noreturn]] void __attribute__((noinline)) ThrowParseException(const char *_ecv_array str) const THROWS(GCodeException);
diff --git a/src/GCodes/GCodeBuffer/StringParser.cpp b/src/GCodes/GCodeBuffer/StringParser.cpp
index 9f9c541bb9..151275b3fc 100644
--- a/src/GCodes/GCodeBuffer/StringParser.cpp
+++ b/src/GCodes/GCodeBuffer/StringParser.cpp
@@ -961,7 +961,7 @@ void StringParser::DecodeCommand() noexcept
 	if (cl == '\'')									// check for a lowercase axis letter in Fanuc mode
 	{
 		++commandStart;
-		cl = tolower(gb.buffer[commandStart]);
+		cl = (char)tolower(gb.buffer[commandStart]);
 	}
 	else
 	{
@@ -1202,7 +1202,7 @@ FilePosition StringParser::GetFilePosition() const noexcept
 	return noFilePosition;
 }
 
-const char* StringParser::DataStart() const noexcept
+const char *_ecv_array StringParser::DataStart() const noexcept
 {
 	return gb.buffer + commandStart;
 }
@@ -1259,7 +1259,7 @@ bool StringParser::Seen(char c) noexcept
 				if (   inBrackets == 0
 					&& (char)toupper(b) == c
 					&& escaped == wantLowerCase
-					&& (c != 'E' || (unsigned int)readPointer == parameterStart || !isdigit(gb.buffer[readPointer - 1]))
+					&& (c != 'E' || (unsigned int)readPointer == parameterStart || !(bool)isdigit(gb.buffer[readPointer - 1]))
 				   )
 				{
 					++readPointer;
@@ -1506,10 +1506,10 @@ void StringParser::InternalGetQuotedString(const StringRef& str) THROWS(GCodeExc
 		}
 		else if (c == '\'')
 		{
-			if (isalpha(gb.buffer[readPointer]))
+			if ((bool)isalpha(gb.buffer[readPointer]))
 			{
 				// Single quote before an alphabetic character forces that character to lower case
-				c = tolower(gb.buffer[readPointer++]);
+				c = (char)tolower(gb.buffer[readPointer++]);
 			}
 			else if (gb.buffer[readPointer] == c)
 			{
@@ -1921,7 +1921,7 @@ bool StringParser::FileEnded() noexcept
 }
 
 // Check that a number was found. If it was, advance readPointer past it. Otherwise throw an exception.
-void StringParser::CheckNumberFound(const char *endptr) THROWS(GCodeException)
+void StringParser::CheckNumberFound(const char *_ecv_array endptr) THROWS(GCodeException)
 {
 	if (endptr == gb.buffer + readPointer)
 	{
@@ -1941,7 +1941,7 @@ float StringParser::ReadFloatValue() THROWS(GCodeException)
 		return val;
 	}
 
-	const char *endptr;
+	const char *_ecv_array endptr;
 	const float rslt = SafeStrtof(gb.buffer + readPointer, &endptr);
 	CheckNumberFound(endptr);
 	return rslt;
@@ -1958,7 +1958,7 @@ uint32_t StringParser::ReadUIValue() THROWS(GCodeException)
 	}
 
 	// Allow "0xNNNN" or "xNNNN" where NNNN are hex digits. We could stop supporting this because we already support {0xNNNN}.
-	const char *endptr;
+	const char *_ecv_array endptr;
 	const uint32_t rslt = StrToU32(gb.buffer + readPointer, &endptr);
 	CheckNumberFound(endptr);
 	return rslt;
@@ -1974,7 +1974,7 @@ int32_t StringParser::ReadIValue() THROWS(GCodeException)
 		return val;
 	}
 
-	const char *endptr;
+	const char *_ecv_array endptr;
 	const int32_t rslt = StrToI32(gb.buffer + readPointer, &endptr);
 	CheckNumberFound(endptr);
 	return rslt;
@@ -2064,7 +2064,7 @@ void StringParser::AddParameters(VariableSet& vs, int codeRunning) THROWS(GCodeE
 										{
 											throw ConstructParseException("invalid value for parameter '%c'", (uint32_t)c);
 										}
-										ExpressionParser parser(gb, &gb.buffer[readPointer], &gb.buffer[commandEnd]);
+										ExpressionParser parser(gb, gb.buffer + readPointer, gb.buffer + commandEnd);
 										ExpressionValue ev = parser.Parse();
 										char paramName[2] = { letter, 0 };
 										vs.InsertNewParameter(paramName, ev);
diff --git a/src/GCodes/GCodeBuffer/StringParser.h b/src/GCodes/GCodeBuffer/StringParser.h
index 6c64b83e5c..4f8cc64158 100644
--- a/src/GCodes/GCodeBuffer/StringParser.h
+++ b/src/GCodes/GCodeBuffer/StringParser.h
@@ -79,7 +79,7 @@ class StringParser
 
 	FilePosition GetFilePosition() const noexcept;							// Get the file position at the start of the current command
 
-	const char* DataStart() const noexcept;									// Get the start of the current command
+	const char *_ecv_array DataStart() const noexcept;						// Get the start of the current command
 	size_t DataLength() const noexcept;										// Get the length of the current command
 
 	void PrintCommand(const StringRef& s) const noexcept;
@@ -107,7 +107,7 @@ class StringParser
 	int32_t ReadIValue() THROWS(GCodeException);
 	DriverId ReadDriverIdValue() THROWS(GCodeException);
 	void CheckArrayLength(size_t actualLength, size_t maxLength) THROWS(GCodeException);
-	void CheckNumberFound(const char *endptr) THROWS(GCodeException);
+	void CheckNumberFound(const char *_ecv_array endptr) THROWS(GCodeException);
 
 	void CheckForMixedSpacesAndTabs() noexcept;
 	bool ProcessConditionalGCode(const StringRef& reply, BlockType skippedBlockType, bool doingFile) THROWS(GCodeException);
diff --git a/src/GCodes/GCodes.cpp b/src/GCodes/GCodes.cpp
index c35621c4e0..167599411e 100644
--- a/src/GCodes/GCodes.cpp
+++ b/src/GCodes/GCodes.cpp
@@ -4451,7 +4451,7 @@ void GCodes::StopPrint(GCodeBuffer *gbp, StopPrintReason reason) noexcept
 		simulationMode = SimulationMode::off;					// do this after we append the simulation info to the file so that DWC doesn't try to reload the file info too soon
 		reprap.GetMove().Simulate(simulationMode);
 		EndSimulation(nullptr);
-		reprap.GetPrintMonitor().StoppedPrint();				// must do this after printing the simulation details not before, because it clears the filename and pause time
+		reprap.GetPrintMonitor().StoppedPrint();
 
 		const uint32_t simMinutes = lrintf(simSeconds/60.0);
 		if (reason == StopPrintReason::normalCompletion)
diff --git a/src/GCodes/GCodes4.cpp b/src/GCodes/GCodes4.cpp
index 76babd3314..340d55f9d5 100644
--- a/src/GCodes/GCodes4.cpp
+++ b/src/GCodes/GCodes4.cpp
@@ -1559,7 +1559,7 @@ void GCodes::RunStateMachine(GCodeBuffer& gb, const StringRef& reply) noexcept
 						ms.checkEndstops = true;
 						ms.reduceAcceleration = true;
 						straightProbeSettings.SetCoordsToTarget(ms.coords);
-						ms.feedRate = zp->GetProbingSpeed(0);
+						ms.feedRate = (straightProbeSettings.GetFeedRateOverride() > 0.0) ? straightProbeSettings.GetFeedRateOverride() : zp->GetProbingSpeed(0);
 						ms.linearAxesMentioned = ms.rotationalAxesMentioned = true;
 						NewSingleSegmentMoveAvailable(ms);
 						gb.AdvanceState();
diff --git a/src/GCodes/GCodes6.cpp b/src/GCodes/GCodes6.cpp
index 00b14a1f16..da1319fb7c 100644
--- a/src/GCodes/GCodes6.cpp
+++ b/src/GCodes/GCodes6.cpp
@@ -659,6 +659,12 @@ GCodeResult GCodes::StraightProbe(GCodeBuffer& gb, const StringRef& reply) THROW
 	}
 	straightProbeSettings.SetZProbeToUse(probeToUse);
 
+	// Check if feed rate has been specified
+	if (gb.Seen('F'))
+	{
+		straightProbeSettings.SetFeedRateOverride(gb.GetSpeedFromMm(false));
+	}
+
 	gb.SetState(GCodeState::straightProbe0);
 	return GCodeResult::ok;
 }
diff --git a/src/GCodes/StraightProbeSettings.cpp b/src/GCodes/StraightProbeSettings.cpp
index c690f9cd27..bb18ef3bf3 100644
--- a/src/GCodes/StraightProbeSettings.cpp
+++ b/src/GCodes/StraightProbeSettings.cpp
@@ -15,6 +15,7 @@ StraightProbeSettings::StraightProbeSettings() noexcept
 
 void StraightProbeSettings::Reset() noexcept
 {
+	feedRateOverride = 0.0;
 	movingAxes = AxesBitmap();
 	type = StraightProbeType::unset;
 	for (size_t axis = 0; axis < MaxAxes; ++axis)
diff --git a/src/GCodes/StraightProbeSettings.h b/src/GCodes/StraightProbeSettings.h
index 4983eac210..8dcbf90937 100644
--- a/src/GCodes/StraightProbeSettings.h
+++ b/src/GCodes/StraightProbeSettings.h
@@ -40,12 +40,16 @@ class StraightProbeSettings
 	const size_t GetZProbeToUse() const noexcept { return probeToUse; }
 	void SetZProbeToUse(const size_t probeNumber) noexcept { probeToUse = probeNumber; }
 
+	const float GetFeedRateOverride() const noexcept { return feedRateOverride; }
+	void SetFeedRateOverride(const float feedRate) noexcept { feedRateOverride = feedRate; }
+
 	const bool ProbingAway() const noexcept;
 	const bool SignalError() const noexcept;
 
 private:
 	AxesBitmap movingAxes;                 // Axes supposed to move - this is only used for manual probing
 	size_t probeToUse;                     // Use this ZProbe
+	float feedRateOverride;                // Feed rate for the probing move
 	float target[MaxAxes];                 // G38 target coordinates for straight probe moves
 	StraightProbeType type;                // Type of move
 };
diff --git a/src/Movement/Move.cpp b/src/Movement/Move.cpp
index 28e22f1d90..e8d9e1711f 100644
--- a/src/Movement/Move.cpp
+++ b/src/Movement/Move.cpp
@@ -355,7 +355,6 @@ Move::Move() noexcept
 	  heightController(nullptr),
 #endif
 	  jerkPolicy(0),
-	  stepErrorState(StepErrorState::noError),
 	  numCalibratedFactors(0)
 {
 #if VARIABLE_NUM_DRIVERS
@@ -2328,12 +2327,18 @@ void Move::AddLinearSegments(const DDA& dda, size_t logicalDrive, uint32_t start
 			{
 				if (tail->GetFlags().executing)
 				{
-					const uint32_t now = StepTimer::GetMovementTimerTicks();
-					const int32_t overlap = endTime - startTime;
+#if 1	// temp for debugging
+					stepErrorDetails.executingStartTime = segStartTime;
+					stepErrorDetails.executingDuration = tail->GetDuration();
+					stepErrorDetails.newSegmentStartTime = startTime;
+					stepErrorDetails.timeNow = StepTimer::GetMovementTimerTicks();
+#endif
 					LogStepError(3);
 					RestoreBasePriority(oldPrio);
 					if (reprap.Debug(Module::Move))
 					{
+						const uint32_t now = StepTimer::GetMovementTimerTicks();
+						const int32_t overlap = endTime - startTime;
 						debugPrintf("overlaps executing seg by %" PRIi32 " while trying to add segment(s) starting at %" PRIu32 ", time now %" PRIu32 "\n",
 										overlap, startTime, now);
 						MoveSegment::DebugPrintList(tail);
diff --git a/src/Movement/Move.h b/src/Movement/Move.h
index 6eb6ae6c57..e43caec49a 100644
--- a/src/Movement/Move.h
+++ b/src/Movement/Move.h
@@ -98,6 +98,16 @@ struct NonlinearExtrusion
 
 #endif
 
+// Collection of data reported to help debug step errors
+struct StepErrorDetails
+{
+	uint32_t executingStartTime;
+	uint32_t executingDuration;
+	uint32_t newSegmentStartTime;
+	uint32_t timeNow;
+	uint8_t stepErrorType;
+};
+
 // This is the master movement class.  It controls all movement in the machine.
 class Move INHERIT_OBJECT_MODEL
 {
@@ -463,7 +473,7 @@ class Move INHERIT_OBJECT_MODEL
 
 	// Movement error handling
 	void LogStepError(uint8_t type) noexcept;												// stop all movement because of a step error
-	uint8_t GetStepErrorType() const noexcept { return stepErrorType; }
+	StepErrorDetails GetStepErrorDetails() const noexcept { return stepErrorDetails; }
 	bool HasMovementError() const noexcept;
 	void ResetAfterError() noexcept;
 	void GenerateMovementErrorDebug() noexcept;
@@ -492,12 +502,12 @@ class Move INHERIT_OBJECT_MODEL
 		timing			// no moves being executed or in queue, motors are at full current
 	};
 
-	enum class StepErrorState : uint8_t
-	{
-		noError = 0,	// no error
-		haveError,		// had an error, movement is stopped
-		resetting		// had an error, ready to reset it
-	};
+enum class StepErrorState : uint8_t
+{
+	noError = 0,	// no error
+	haveError,		// had an error, movement is stopped
+	resetting		// had an error, ready to reset it
+};
 
 #if SUPPORT_SCANNING_PROBES
 	struct ScanningProbeControl
@@ -665,9 +675,6 @@ class Move INHERIT_OBJECT_MODEL
 
 	float specialMoveCoords[MaxDriversPerAxis];			// Amounts by which to move individual Z motors (leadscrew adjustment move)
 
-	volatile uint8_t stepErrorType;
-	volatile StepErrorState stepErrorState;
-
 	// Drives
 #if VARIABLE_NUM_DRIVERS && SUPPORT_DIRECT_LCD
 	size_t numActualDirectDrivers;
@@ -765,6 +772,10 @@ class Move INHERIT_OBJECT_MODEL
 	bool bedLevellingMoveAvailable;						// True if a leadscrew adjustment move is pending
 	bool usingMesh;										// True if we are using the height map, false if we are using the random probe point set
 	bool useTaper;										// True to taper off the compensation
+
+	// Reporting of step errors
+	volatile StepErrorState stepErrorState = StepErrorState::noError;
+	StepErrorDetails stepErrorDetails;
 };
 
 //******************************************************************************************************
@@ -982,7 +993,7 @@ inline void Move::InsertDM(DriveMovement *dm) noexcept
 
 inline void Move::LogStepError(uint8_t type) noexcept
 {
-	stepErrorType = type;
+	stepErrorDetails.stepErrorType = type;
 	stepErrorState = StepErrorState::haveError;
 }
 
diff --git a/src/Movement/RawMove.h b/src/Movement/RawMove.h
index a48d9d95df..5a8c7b7536 100644
--- a/src/Movement/RawMove.h
+++ b/src/Movement/RawMove.h
@@ -55,7 +55,7 @@ struct RawMove
 	// If adding any more fields, keep the total size a multiple of 4 bytes so that we can use our optimised assignment operator
 
 	// GCC normally calls memcpy to assign objects of this class. We can do better because we know they must be 32-bit aligned.
-	RawMove& operator=(const RawMove& arg) noexcept
+	RawMove &_ecv_from operator=(const RawMove& arg) noexcept
 	{
 		memcpyu32(reinterpret_cast<uint32_t *_ecv_array>(this), reinterpret_cast<const uint32_t *_ecv_array>(&arg), sizeof(*this)/4);
 		return *this;
diff --git a/src/Platform/Platform.cpp b/src/Platform/Platform.cpp
index 6377e47bc3..83058abcdf 100644
--- a/src/Platform/Platform.cpp
+++ b/src/Platform/Platform.cpp
@@ -893,7 +893,15 @@ void Platform::Spin() noexcept
 	Move& move = reprap.GetMove();
 	if (move.HasMovementError())
 	{
-		MessageF(AddError(MessageType::GenericMessage), "Movement halted because a step timing error occurred (code %u). Please reset the controller.\n", move.GetStepErrorType());
+		const StepErrorDetails details = move.GetStepErrorDetails();
+		MessageF(AddError(MessageType::GenericMessage), "Movement halted because a step timing error occurred (code %u). Please reset the controller.\n", details.stepErrorType);
+		if (details.stepErrorType == 3)
+		{
+			MessageF(AddError(MessageType::GenericMessage), "Existing: start=%" PRIu32 " length=%" PRIu32 ", new: start=%" PRIu32 ", overlap=%" PRIu32 " time now=%" PRIu32 "\n",
+						details.executingStartTime, details.executingDuration, details.newSegmentStartTime,
+						details.executingStartTime + details.executingDuration - details.newSegmentStartTime,
+						details.timeNow);
+		}
 		move.GenerateMovementErrorDebug();
 		move.ResetAfterError();
 	}