I tried to update to the latest NB (25th February).
Since the NB comes only as a complete (installation) package I did this manually based on an existing DB(unpack the package, upload / overwrite the files).
The last times it worked well, but this time fails. I get an error in the admin which seems to be related to the DB (ps_database.php).
So does the nightly build also affect / change the DB?
We usually don't change database structure during minor updates, only bug fixes, the error you get is due to a change in code, hence is not recommended to use nightly builds on production site only for testing and feedback.