...window-latches towards the top position by hand: This will automatically pull in the motor spindle! And then put everything back into the door. So I assembled everything again and put the window back in (while the regulator was close to top position, which was possible but made things very difficult, as it is a lot easier with the regulator half way down). Again: Think a few steps ahead not to damage the glass. SO I thought the regulator must have been stuck somehow and I fixed it.