I tried converting to a user app with Titanium Backup, but that failed (Cannot convert "Samsung keyboard 1.0" to a user app.) I backed up the keyboard with Titanium Backup and copied the apk out of /system/data, then uninstalled the keyboard. I tried installing the apk from ES File Explorer, but that appeared to fail silently - I couldn't select it in Settings. Then I went to Google Play and was going to install from there, but the only choice was to Uninstall, so I did that. Then the option was Update. I tried updating, and again no obvious way to see anything installed.
Last, I restored from Titanium Backup, and I'm back where I started.
1) Is there a way to change an installed app from a system app to a user app, given Titanium Backup failed?
2) Is there a way to modify a Titanium Backup backup to change it from a system to a user app?