Problem installing a .pbw with Pebble Time files on v2.9; works after removing them from the archive

[eras]

Edit: I just realized the files are not superfluous at all but rather different versions for Pebble Time I think :). In any case, I'm still on the old v2.9 and my Pebble Jolla app version is 1.4-1.

I tried to install Alarm++ from the store, but Pebble gave the message

syys 21 11:11:34 Jolla pebbled[1732]: [W] BankManager::uploadApp:85 - failed to open "Alarms++" AppInfo::BINARY 

I noticed that the contents of the .pbw was:

[nemo@Jolla apps]$ unzip -v e3060014-bfe9-4d03-b75e-374cc4dca97b.pbw 
Archive:  e3060014-bfe9-4d03-b75e-374cc4dca97b.pbw
 Length   Method    Size  Cmpr    Date    Time   CRC-32   Name
--------  ------  ------- ---- ---------- ----- --------  ----
    2471  Stored     2471   0% 09-04-2015 22:21 2cd76dee  appinfo.json
   16828  Stored    16828   0% 09-04-2015 22:22 2a1a8233  basalt/pebble-app.bin
   10271  Stored    10271   0% 09-04-2015 22:21 39890b0c  basalt/app_resources.pbpack
     368  Stored      368   0% 09-04-2015 22:22 e02e9768  basalt/manifest.json
   15180  Stored    15180   0% 09-04-2015 22:22 53d6882f  pebble-app.bin
    9970  Stored     9970   0% 09-04-2015 22:21 015124d9  app_resources.pbpack
     367  Stored      367   0% 09-04-2015 22:22 a760ff7a  manifest.json
--------          -------  ---                            -------
   55455            55455   0%                            7 files

After issuing

[nemo@Jolla apps]$ zip -d e3060014-bfe9-4d03-b75e-374cc4dca97b.pbw basalt/pebble-app.bin basalt/app_resources.pbpack basalt/manifest.json

the problem went away and the package installed the first time I tried. I can only guess this works with old Pebbles with Pebble software, but I don't know if they author still supports them..