The plastic shell shifting is because things aren't lined up right. The way they've designed the case is so it is easy to open...but as a result of the design, it allows for a lot of twisting which means it won't sit right, the case will be loose in some areas...
BUT, you can fix it all...Put your RF on a flat surface and press on all four corners at the same time really hard..this will set it all in the right position..you may need to twist it around a bit but eventually it'll all sit right.
I'm not sure why they designed it that way but it does cause some confusion and upset people...really though, it is easy to "fix".