diff --git a/docs/source/bundle.rst b/docs/source/bundle.rst
index 94ca8813f4..7942e4d349 100644
--- a/docs/source/bundle.rst
+++ b/docs/source/bundle.rst
@@ -48,3 +48,4 @@ Model Bundle
 .. autofunction:: verify_metadata
 .. autofunction:: verify_net_in_out
 .. autofunction:: init_bundle
+.. autofunction:: update_kwargs
diff --git a/monai/bundle/__init__.py b/monai/bundle/__init__.py
index 711f1d2875..bd5db3cbea 100644
--- a/monai/bundle/__init__.py
+++ b/monai/bundle/__init__.py
@@ -29,6 +29,7 @@
     run,
     run_workflow,
     trt_export,
+    update_kwargs,
     verify_metadata,
     verify_net_in_out,
 )
diff --git a/monai/bundle/config_parser.py b/monai/bundle/config_parser.py
index 990ff00a42..829036af6f 100644
--- a/monai/bundle/config_parser.py
+++ b/monai/bundle/config_parser.py
@@ -412,13 +412,16 @@ def load_config_files(cls, files: PathLike | Sequence[PathLike] | dict, **kwargs
 
         Args:
             files: path of target files to load, supported postfixes: `.json`, `.yml`, `.yaml`.
-                if providing a list of files, wil merge the content of them.
+                if providing a list of files, will merge the content of them.
+                if providing a string with comma separated file paths, will merge the content of them.
                 if providing a dictionary, return it directly.
             kwargs: other arguments for ``json.load`` or ```yaml.safe_load``, depends on the file format.
         """
         if isinstance(files, dict):  # already a config dict
             return files
         parser = ConfigParser(config={})
+        if isinstance(files, str) and not Path(files).is_file() and "," in files:
+            files = files.split(",")
         for i in ensure_tuple(files):
             for k, v in (cls.load_config_file(i, **kwargs)).items():
                 parser[k] = v
diff --git a/monai/bundle/scripts.py b/monai/bundle/scripts.py
index c3aec09b5e..4607ef65b7 100644
--- a/monai/bundle/scripts.py
+++ b/monai/bundle/scripts.py
@@ -66,33 +66,46 @@
 PPRINT_CONFIG_N = 5
 
 
-def _update_args(args: str | dict | None = None, ignore_none: bool = True, **kwargs: Any) -> dict:
+def update_kwargs(args: str | dict | None = None, ignore_none: bool = True, **kwargs: Any) -> dict:
     """
-    Update the `args` with the input `kwargs`.
+    Update the `args` dictionary with the input `kwargs`.
     For dict data, recursively update the content based on the keys.
 
+    Example::
+
+        from monai.bundle import update_kwargs
+        update_kwargs({'exist': 1}, exist=2, new_arg=3)
+        # return {'exist': 2, 'new_arg': 3}
+
     Args:
-        args: source args to update.
+        args: source `args` dictionary (or a json/yaml filename to read as dictionary) to update.
         ignore_none: whether to ignore input args with None value, default to `True`.
-        kwargs: destination args to update.
+        kwargs: key=value pairs to be merged into `args`.
 
     """
     args_: dict = args if isinstance(args, dict) else {}
     if isinstance(args, str):
         # args are defined in a structured file
         args_ = ConfigParser.load_config_file(args)
+    if isinstance(args, (tuple, list)) and all(isinstance(x, str) for x in args):
+        primary, overrides = args
+        args_ = update_kwargs(primary, ignore_none, **update_kwargs(overrides, ignore_none, **kwargs))
+    if not isinstance(args_, dict):
+        return args_
     # recursively update the default args with new args
     for k, v in kwargs.items():
-        print(k, v)
         if ignore_none and v is None:
             continue
         if isinstance(v, dict) and isinstance(args_.get(k), dict):
-            args_[k] = _update_args(args_[k], ignore_none, **v)
+            args_[k] = update_kwargs(args_[k], ignore_none, **v)
         else:
             args_[k] = v
     return args_
 
 
+_update_args = update_kwargs  # backward compatibility
+
+
 def _pop_args(src: dict, *args: Any, **kwargs: Any) -> tuple:
     """
     Pop args from the `src` dictionary based on specified keys in `args` and (key, default value) pairs in `kwargs`.
@@ -318,7 +331,7 @@ def download(
             so that the command line inputs can be simplified.
 
     """
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         name=name,
         version=version,
@@ -834,7 +847,7 @@ def verify_metadata(
 
     """
 
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         meta_file=meta_file,
         filepath=filepath,
@@ -958,7 +971,7 @@ def verify_net_in_out(
 
     """
 
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         net_id=net_id,
         meta_file=meta_file,
@@ -1127,7 +1140,7 @@ def onnx_export(
             e.g. ``--_meta#network_data_format#inputs#image#num_channels 3``.
 
     """
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         net_id=net_id,
         filepath=filepath,
@@ -1242,7 +1255,7 @@ def ckpt_export(
             e.g. ``--_meta#network_data_format#inputs#image#num_channels 3``.
 
     """
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         net_id=net_id,
         filepath=filepath,
@@ -1401,7 +1414,7 @@ def trt_export(
             e.g. ``--_meta#network_data_format#inputs#image#num_channels 3``.
 
     """
-    _args = _update_args(
+    _args = update_kwargs(
         args=args_file,
         net_id=net_id,
         filepath=filepath,
@@ -1614,7 +1627,7 @@ def create_workflow(
         kwargs: arguments to instantiate the workflow class.
 
     """
-    _args = _update_args(args=args_file, workflow_name=workflow_name, config_file=config_file, **kwargs)
+    _args = update_kwargs(args=args_file, workflow_name=workflow_name, config_file=config_file, **kwargs)
     _log_input_summary(tag="run", args=_args)
     (workflow_name, config_file) = _pop_args(
         _args, workflow_name=ConfigWorkflow, config_file=None
diff --git a/monai/bundle/workflows.py b/monai/bundle/workflows.py
index 585553a806..da3aa30141 100644
--- a/monai/bundle/workflows.py
+++ b/monai/bundle/workflows.py
@@ -14,7 +14,6 @@
 import os
 import sys
 import time
-import warnings
 from abc import ABC, abstractmethod
 from copy import copy
 from logging.config import fileConfig
@@ -158,7 +157,7 @@ def add_property(self, name: str, required: str, desc: str | None = None) -> Non
         if self.properties is None:
             self.properties = {}
         if name in self.properties:
-            warnings.warn(f"property '{name}' already exists in the properties list, overriding it.")
+            logger.warn(f"property '{name}' already exists in the properties list, overriding it.")
         self.properties[name] = {BundleProperty.DESC: desc, BundleProperty.REQUIRED: required}
 
     def check_properties(self) -> list[str] | None:
@@ -241,7 +240,7 @@ def __init__(
             for _config_file in _config_files:
                 _config_file = Path(_config_file)
                 if _config_file.parent != self.config_root_path:
-                    warnings.warn(
+                    logger.warn(
                         f"Not all config files are in {self.config_root_path}. If logging_file and meta_file are"
                         f"not specified, {self.config_root_path} will be used as the default config root directory."
                     )
@@ -254,7 +253,7 @@ def __init__(
         if logging_file is not None:
             if not os.path.exists(logging_file):
                 if logging_file == str(self.config_root_path / "logging.conf"):
-                    warnings.warn(f"Default logging file in {logging_file} does not exist, skipping logging.")
+                    logger.warn(f"Default logging file in {logging_file} does not exist, skipping logging.")
                 else:
                     raise FileNotFoundError(f"Cannot find the logging config file: {logging_file}.")
             else:
@@ -265,7 +264,10 @@ def __init__(
         self.parser.read_config(f=config_file)
         meta_file = str(self.config_root_path / "metadata.json") if meta_file is None else meta_file
         if isinstance(meta_file, str) and not os.path.exists(meta_file):
-            raise FileNotFoundError(f"Cannot find the metadata config file: {meta_file}.")
+            logger.error(
+                f"Cannot find the metadata config file: {meta_file}. "
+                "Please see: https://docs.monai.io/en/stable/mb_specification.html"
+            )
         else:
             self.parser.read_meta(f=meta_file)
 
@@ -323,17 +325,17 @@ def check_properties(self) -> list[str] | None:
         """
         ret = super().check_properties()
         if self.properties is None:
-            warnings.warn("No available properties had been set, skipping check.")
+            logger.warn("No available properties had been set, skipping check.")
             return None
         if ret:
-            warnings.warn(f"Loaded bundle does not contain the following required properties: {ret}")
+            logger.warn(f"Loaded bundle does not contain the following required properties: {ret}")
         # also check whether the optional properties use correct ID name if existing
         wrong_props = []
         for n, p in self.properties.items():
             if not p.get(BundleProperty.REQUIRED, False) and not self._check_optional_id(name=n, property=p):
                 wrong_props.append(n)
         if wrong_props:
-            warnings.warn(f"Loaded bundle defines the following optional properties with wrong ID: {wrong_props}")
+            logger.warn(f"Loaded bundle defines the following optional properties with wrong ID: {wrong_props}")
         if ret is not None:
             ret.extend(wrong_props)
         return ret
diff --git a/monai/data/meta_tensor.py b/monai/data/meta_tensor.py
index 9e93b3935e..cad0851a8e 100644
--- a/monai/data/meta_tensor.py
+++ b/monai/data/meta_tensor.py
@@ -462,7 +462,7 @@ def astype(self, dtype, device=None, *_args, **_kwargs):
     @property
     def affine(self) -> torch.Tensor:
         """Get the affine. Defaults to ``torch.eye(4, dtype=torch.float64)``"""
-        return self.meta.get(MetaKeys.AFFINE, self.get_default_affine())
+        return self.meta.get(MetaKeys.AFFINE, self.get_default_affine())  # type: ignore
 
     @affine.setter
     def affine(self, d: NdarrayTensor) -> None:
diff --git a/runtests.sh b/runtests.sh
index bdd56f8de3..cfceb6976a 100755
--- a/runtests.sh
+++ b/runtests.sh
@@ -108,7 +108,7 @@ function print_usage {
     echo "    -c, --clean       : clean temporary files from tests and exit"
     echo "    -h, --help        : show this help message and exit"
     echo "    -v, --version     : show MONAI and system version information and exit"
-    echo "    -p, --path        : specify the path used for formatting"
+    echo "    -p, --path        : specify the path used for formatting, default is the current dir if unspecified"
     echo "    --formatfix       : format code using \"isort\" and \"black\" for user specified directories"
     echo ""
     echo "${separator}For bug reports and feature requests, please file an issue at:"
@@ -359,10 +359,9 @@ if [ -e "$testdir" ]
 then
     homedir=$testdir
 else
-    print_error_msg "Incorrect path: $testdir provided, run under $currentdir"
     homedir=$currentdir
 fi
-echo "run tests under $homedir"
+echo "Run tests under $homedir"
 cd "$homedir"
 
 # python path
diff --git a/tests/test_bundle_utils.py b/tests/test_bundle_utils.py
index 391a56bc3c..181c08475c 100644
--- a/tests/test_bundle_utils.py
+++ b/tests/test_bundle_utils.py
@@ -18,6 +18,7 @@
 
 import torch
 
+from monai.bundle import update_kwargs
 from monai.bundle.utils import load_bundle_config
 from monai.networks.nets import UNet
 from monai.utils import pprint_edges
@@ -141,6 +142,7 @@ def test_str(self):
             "[{'a': 1, 'b': 2},\n\n ... omitted 18 line(s)\n\n {'a': 1, 'b': 2}]",
         )
         self.assertEqual(pprint_edges([{"a": 1, "b": 2}] * 8, 4), pprint_edges([{"a": 1, "b": 2}] * 8, 3))
+        self.assertEqual(update_kwargs({"a": 1}, a=2, b=3), {"a": 2, "b": 3})
 
 
 if __name__ == "__main__":
diff --git a/tests/test_integration_bundle_run.py b/tests/test_integration_bundle_run.py
index fb9e0e75c6..bd96f50c55 100644
--- a/tests/test_integration_bundle_run.py
+++ b/tests/test_integration_bundle_run.py
@@ -86,9 +86,8 @@ def test_tiny(self):
         with self.assertRaises(RuntimeError):
             # test wrong run_id="run"
             command_line_tests(cmd + ["run", "run", "--config_file", config_file])
-        with self.assertRaises(RuntimeError):
-            # test missing meta file
-            command_line_tests(cmd + ["run", "training", "--config_file", config_file])
+        # test missing meta file
+        self.assertIn("ERROR", command_line_tests(cmd + ["run", "training", "--config_file", config_file]))
 
     def test_scripts_fold(self):
         # test scripts directory has been added to Python search directories automatically
@@ -150,9 +149,8 @@ def test_scripts_fold(self):
         print(output)
         self.assertTrue(expected_condition in output)
 
-        with self.assertRaises(RuntimeError):
-            # test missing meta file
-            command_line_tests(cmd + ["run", "training", "--config_file", config_file])
+        # test missing meta file
+        self.assertIn("ERROR", command_line_tests(cmd + ["run", "training", "--config_file", config_file]))
 
     @parameterized.expand([TEST_CASE_1, TEST_CASE_2])
     def test_shape(self, config_file, expected_shape):
diff --git a/tests/utils.py b/tests/utils.py
index 9f2b41adb7..a8efbe081e 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -818,6 +818,7 @@ def command_line_tests(cmd, copy_env=True):
     try:
         normal_out = subprocess.run(cmd, env=test_env, check=True, capture_output=True)
         print(repr(normal_out).replace("\\n", "\n").replace("\\t", "\t"))
+        return repr(normal_out)
     except subprocess.CalledProcessError as e:
         output = repr(e.stdout).replace("\\n", "\n").replace("\\t", "\t")
         errors = repr(e.stderr).replace("\\n", "\n").replace("\\t", "\t")