The Malf State thing worked for me, thanks again!
I could mount the file system and recover the /usr/share/swype/data directory.
Now the keyboard works fine again.
Obiviously something was changed in the phone settings as well, because the phone boots up without lock-screen now...
I mean, my only intention was to recover the keyboard, but I also accidently removed the password prompt without any authentication, mh.
Ok, of course the password doesn't really protect the data because one can easily mount the unencryptet filesystem anyways. On the other hand, I hope we will see an option to have the filesystem encrypted anytime soon in Jolla Sailfish...
Best regards and thanks again,

Chris