1. The emulator itself doesnt use any of the consoles code. It is all made form scratch.
3. CXBX runs Turok Evolution very well and Xeon can boot Halo (not playable as there are alot of gfx bugs ingame). Those are the only games that i know of that show something
4. We all want a fully playable emu

Caustik (author of CXBX) has already approached __SF__ (author of Xeon). It seems that they wont be working on the same emu. now it doesnt mean that they cant share info.