1. I have, many others did as well.
2. Not very difficult at all. You need to keep the original boards in nicely tugged place and make sure the ribbons are secured always, otherwise you'll get lots of weird problems like auto turn on does not work, color problems, lines...etc.
3. No custom bezel that i know of, but you can make your own by cutting your case and modify it using bondo/fibreglass...other products.
4. There's the touchscreen controller which is a board about 1"x2.5" and it sits behind the screen, and the touchscreen overlay which is the glass panel you touch.
5. I'm pretty sure it has mac support, double check on it though.
6. Xenarc is very nice, and it works great, I don't have anything against it really, but if you want an alternative, the lilliput 629 is very nice as well (bright, easy mod, slim casing).