To be honest you havent really given enough information. For starters, you said you have installed the XBIT correctly and it is booting to the MS Dashboard, is it using the Original BIOS, or have you flashed hacked BIOS to the XBIT as it doesnt come with any pre-flashed.
If you havent flashed any hacked BIOS, it doesnt matter how many times you burn an EVOX cdrw as it isnt going to boot, due to the code.
If you have flashed hacked BIOS, which one/ones are you using, you should either use an Executer BIOS, or a colour changed EVOX M7 BIOS (using XBTool, to change the XBOX Logo & TEXT Colour) prior to flashing to XBIT. Either of these will then show you that you have a Hacked BIOS loaded. Executer 2 by the fact that the word MS is changed to Executer 2 under the XBOX logo, and the Evox M7 one, because the Colours are different.
You really need to make sure you have a hacked BIOS running before you can go any further.
Yours
Spice Guy