electric window madness!

Hi, I have an annoying problem with my A4 (2002) 1.9TDi. The drivers side electric window was intermittently working, when it did work it worked fully, and when it didn't it just wouldn't work at all. Now it is in a state of very not working. The drivers side control for the passenger window works fine. I took the door panel off to have a play around, cleaned what I could of the sealed switch unit. Smacked the winding motor with a hammer etc. Checked the fuses. Nothing worked, so I put the panel back on, and hey presto, not only is the drivers side not working, the passenger side control for the passenger side window is not working now either, although the drivers side control for the passenger side window is working. I refuse to let this beat me, and have to take my nearly new car to some over priced dealer to fix it. Please HELP!!!! p.s. I also accidentally put unleaded in the tank, which got flushed today, and now the blooming fuel gauge is showing 1/2 full when the tank is nearly empty.....grrrrrr.......(bad day)