Originally Posted by eiffel

For me the top part fits snugly and is 100% stable - it hasn't come off at all.

Slide the keyboard open, turn the device over, and look for the two tiny plastic lugs that hold it in place. Do you need to push the top cover on a bit harder so that those lugs will clip over the edge of the N900? There lugs on the opposite edge of the top cover are not so easy to inspect.