I was able to reproduce and fix the issue about the time zone but I was not able to produce the problem about not being able to sign in, maybe that is pgsql specific, I will try that next.
The issue about the timezone was a bug where the control for the old time zone system was shown instead of the new one. The fix for this is in the repository, but to show the timezone on registration you will need to uncomment the new timezone control in the mojoProfile.config
Maybe you can try the latest code and see if ti works better for you. I will post again after I try it with pgsql, but it worked correctly so far testing with MS SQL.