I just updated from 0.2.28 to 0.2.32 and can’t login anymore: I’m always redirected to the login page again without any error message.
The update-process went smooth and without error. Renaming/recreating config.inc.php didn’t solve the problem. Login to 0.2.28 was fine, too, so it’s not a lost/misspelled user/password.
Maybe you should try the upgrade step by step. From .28 to .29, then .30 and so on.
Do you have a FTP-Server? Send me a PM with the login data and I will upload some versions. I don´t have .30, but maybe it will work from .29 to .31.