alright! ill try help you out the best i can
1. heres the link to an install for GROM on an is300
http://www.lexusownersclub.co.uk/forum/index.php?showtopic=46731
but your dash SHOULD be a bit different to take apart because its is200
to save you the time i took some pictures for you of how you do mine which should be the same
basically you just use a trim tool (try a taped up flat blade screw driver if you dont have one) to separate the aircon/tray from the rest of the dash
after this you can follow the tutorial, obviously skipping the sat nav wiring bit
hopefully thatll help you get that issue sorted
2. no they are not, this will explain (sorry for no link, for some reason it wouldnt let me link it properly) http://tiny.cc/6gqp8
3. this is a DIY on blacking your headlights http://www.clublexus.com/forums/is-first-generation/205644-diy-info-black-headlight-mod.html
4. youll find the fuse for the foglights in the passenger side foot area behind the panel there, the back of the cover will tell you which one it is
hope this all helps!
Odyssey