Funny stuff. Was about to write a "everything okay now" posting, but while trying to send it I dropped off the site.
It required me 3 cache cleares (why it had to be three is beyond me) and about 12-15 logins to remain stable on the site, I keep getting thrown out at times.
I still wonder if it is connected with being logged into Facebook while NOT using the facebook login here in buzzerbeater - I think I recall all my site problems started back then when the facebook login came.
Nevertheless - original problem seems solved (and most likely on my side), so thanks for now and closed.
Zwei Dinge sind unendlich, die Dummheit und das All...