cforms II form settings not showing

provider: 1and1.com
plugins: Akismet, My Page Order, Picasa Widget, WordPress.com stats, WP-Polls, cforms II

I already increased the memory size using php.ini, tried 20MB and 80MB, but somehow the form settings of cforms II are not showing. It used to work, and I didn’t add or update plugins. I cannot change the forms now, which prevents me from repairing an error on a form. The forms do work on the site. I still can access the global settings, styling and help in the admin panel. Feels like a memory problem, but the php.ini trick worked before. Did 1and1.com change anything, maybe?

Any help is highly appreciated!

Cheers,
Ronnie