I tested a little more. Things I did:
1. disabled bootflag and rebooted
2. removed battery grip
3. Formated cf card (and removed ML)
4. cleared canon settings
5. cleared C.Fn funktions
6. Made these install steps:
http://wiki.magiclantern.fm/installStill get blinking frames.
I tested with disabled Auto lighting optimizer and ML Live View.
Enabled Auto lighting optimizer and ML Live View
and enabled Auto lighting optimizer and Canon Live View. First blink frame appeared after 1:05 minutes.
No blinking frame with disabled Auto lighting optimizer and Canon Live View...
yet!Seems like I got a bad camera model
