But after a few resets I found the reason... I had turned of cellular data ;) Now everything works smoothly and I have a shiny whole screen. I only wish I had bought a battery at the same time, so I could have improved the lifetime for my device a bit more. Cheers.
Did the whole fix, and everything seems to be working fine exept the phone can't find any network. It is stuck searching. I reopened the phone and checked the antenna conection, but I can't see anything wrong with it.
The fastening on the board came loose when trying to remove screw the 1.2 mm Phillips screw. So the screw hole for that screw is still attached to the cover that I removed.