two things

The weather strip on the rear side door by the wheel well is coming off. What can I use to glue it back so It won't come off again? Also, Is the rear cargo door glass really glass or is it a thick plastic? The reason that I ask that is because I want to use a light compound polish to get the waterspots off and I think that would scratch plastic.

Use 3m double stick foam tape for the trim amd yes its a glass hatch on my 02 tb

the foam tape MIGHT work, but I repaired mine on both sides with #M Black Weatherstrip Adhesive. Just make sure you clean the inside groove of the weatherstrip rreally good, a lot of dirt and debris had gathered in mine. Also, clean off the metal edge where the weatherstrip fits on. then just run a thin bead of adhesive on the metal or down in the rubber grrove, slide the weatherstrip back on, and keep on 'blazin'! ;)