I don’t think I’ve done/built anything wrong, but I can’t get the top piece of the case on properly without depressing the buttons constantly. They just seem to be too tall. Here’s some bad pics trying to show the problem:
No, that doesn’t look right— that appears to be a kitting error. Please contact customer service directly and we can send you replacements. In the mean time, if you like, you should be able to trim the buttons down a little using clippers; the same kind that you use for trimming wire leads. The top acrylic plate should be able to fit parallel to the bottom plate, and make the buttons work well.