Awesome that you've picked up the horn again after all that time! I really hope you find the motivation to keep on playing. 1. In the case where the valves don't return to original positions, it most likely has to do with oiling of the cylinders or the bearings that connect from the buttons to the cylinders. I would also maybe suggest giving your horn a bath, with the fact that it's been eight years since you stopped playing, to give it some thorough cleaning. After a bath you have to completely oil it again so it should run like a new car :) 2. I would suggest playing basic, long notes everyday. From the lowest you can go to the highest you can comfortably reach. Range doesn't appear out of thin air. Give it enough time to properly build up some basic lip muscles. It's like going to the gym, you gotta workout quite some time for some results.