How do I restore my app (K-9 Mail) settings from an adb backup?

Question

I just installed Cyanogenmod on my Samsung Galaxy Note. Before doing so I created a backup with adb:

adb backup -all

For some of my apps I want to restore settings. Most importantly that would be K-9 Mail. Thus I unpacked the backup:

java -jar android-backup-extractor-20140630-bin/abe.jar unpack backup.ab backup.tar

Then I deleted most folders which I don't want to restore but I did not delete apps/apps/com.fsck.k9. Then I packed the file again using android back extractor and ran adb restore after I installed K-9 Mail. I was prompted for consent on my phone which I accepted and I was told that the restore was successful. However when I start K-9 Mail I am just greeted with the default welcome screen as if no configuration would be present. I also tried the same with WhatsApp and Viber but both showed the same behaviour.

Next I tried to just copy the k9 mail settings folder using USB connection using a file manager (dolphin). But still no success.

Then I tried to copy the settings using adb push apps/com.fsck.k9 /data/data/com.fsck.k9 (described by someone here) which failed with file or directory not found error. After further googling I tried again but ran adb root before and then that worked. However k9 still greets me with obviously no settings. Since the same source I googled for that idea stated something about a fix_permission script (where I have no idea where that comes from) I googled for fix_permission and found this app installed it and ran it. However still no change.

How is the restore done correctly?

Answer 1

OK, some googleing later I found Titanum Backup and that it supports restoring selectively from adb backups. I copied the backup to my SD-Card and then restored using Titanum Backup and and just worked. (However I'd still be interested in what I missed in the first place).

Note however that the free version does not support restore from adb files.