Magic Mouse Scrolling Stopped working on iMac

Hello everyone, I have a slightly weird Problem.
I went on vacation on 23.12. I shut down my mac and everything worked fine. I came back about 7 days later. Started my mac and the magic mouse stopped scrolling.
No Vertical Scrolling, no horizontal scrolling no changing between pages with single finger swipes. Smart Zoom and double finger tipping and double finger swiping into the dashboard into the Mission Control still works.

What I did till now:
Rebooting, deleting com.apple.systempreferences.plist +reboot, deleting com.apple.driver.AppleBluetoothMultitouch.mouse.plist + reboot, making a new account to try it in.
Nothing of that worked
Yesterday I did a recovery installation of Lion. Inside the recovery Program the scrolling worked again, after the installation it worked too. Today I launched my mac and it stopped working again.
From here on I did the following
Rebooting, deleting com.apple.systempreferences.plist +reboot, deleting com.apple.driver.AppleBluetoothMultitouch.mouse.plist + reboot, installed magicprefs and activated vertical scrolling in there

Didn't help, still not working. I added the files how my mouse preferences and magicpref preferences look. It seems to me that the first one doesn't look like it should.



I got my iMac27 Mid 2011 with Lion preinstalled. everything worked fine apart from the mouse sometimes disconnecting but not that often that I would be worried

 

nope i live in central europe, only thing that MIGHT have to do with this is that it was around 10°C in the room where my iMac is while I was on vacation (I turned the heating system down)

The dirt that comes from using I usually clean with a fibre cloth and a cleaning liquid for TFT Screens, Camera lenses and such.

oh maybe important. magicprefs does see where I put my fingers and also the movement when I switch to realtime.

 

so just for testing it I again booted into recovery mode, launched the Log, and the scrolling works in there.

Booting back into normal mode, it doesn't work wtf is wrong?