Confused with my new Cabrio!
 

I just bought a 95 Cabrio, first Volkswagen I've owned. Everything is great other then a couple problems.

1. The trunk doesn't open.. The push button i think is pushing too far into the trunk and it isn't releasing any latch. The key will turn but nothing opens. How could I fix this?

2. This is the confusing part. My temperature is either running too low, or its overheating. When I drive the vehicle, the needle is below 70C even after running for a half hour. If I stop and sit with the car idling, or I drive slow for a long period of time (parking lots) the needle will start to climb. It climbed to about 90C when I shut it off. I think that's where it's supposed to sit but when I start driving, the needle will go down to below 70C again. Coolant level is where it should be. What could be causing this?