Device won't wakeup from power button I used a Navigator app that prevents my device (Galaxy S2 with Cyanogenmod) from turning the screen off while plugged in. But at some point I could no longer wakeup the device screen with the power button anymore. The only thing that wakes up the device screen is to plug it into a USB charger. This behavior continues even after uninstalling the app. The device is not turned off, it's just the screen wakeup from the power button that stopped working.
I assume that the app overwrote some settings.
I couldn't get any help from developers of app. 

Thanks for any help!
If you unlock the developer options (if not already unlocked with Cyanogenmod), there is an option "Stay awake" that will keep your screen turned on when plugged in.  You can try using that and see if it will revert any settings that the app might have changed.

See this website for a brief explanation on how to enable developer options.

If that doesn't work, you can "remap" the power button back to the power button.  Check out this guide to remap the buttons on your phone.  Hopefully it won't come to this though