First of all, thanks a lot for your reply.
I donīt only speak about the backup, but also about the demo from the original "Move" disc that worked before when FW 3.50 was running.
Is there any reason to assume that this is a downgrade bug? I have searched several forums and websites and have found no one complaining that the EyeToy does not work anymore. To be honest, I have seen more people saying that Sports Champions does work, thatīs why I am really confused now.
The Move controller itself works as I can navigate through the menu - seem to be accelerators that work without the camera.
Next, I am going to check your hints. Unfortunately, I am new to the PS3 scene, so: How do I download the 3.41 again using the system menu? I thought that any firmware menu in the XMB will download the latest FW 3.55...
I reinstalled an unmodded FW 3.41 and rebuilt the database - both ideas unfortunately did not work. The demo of Sports Champions still claims at the beginning that the EyeToy has been unplugged and that I should reconnect it.