i shortly did set 'keep launcher in memory', 'remove unused images' (translated from german) and 'use 16bit for transparency' in cyanogen settings, to tweak it a bit. since then i got only reboots and freezes, shortly after booting.
did those freezes/reboots before occasionaly, but now it got insane!
version 184.108.40.206 and nb221
i made a logcat after a freeze, its full of errors. ill send it on request!
managed to disable that stuff during reboots (seems like it was possible since the PIN requester didnt pop up) now it was working longer. But on first display timeout it froze again. something is seriously bugged with the latest versions.
still reboots and freezes... only thing that seem to have stopped it again was to remove sdcard. so i guess .android_secure is faulty again. But this must have happened during use, not from flashing the ROM, since after flashing it was fine. It only happened after yesterday.
And no, i didnt touch CPU settings. Just moved some more apps to sdcard and changed the above settings (which i reverted as i wrote).
So my conclusion: there is a bug that breaks the .android_secure !