So, I want to play Doom 3 very badly. But the release I found that was made xtreme compatible for the 360 is not iXtreme compatible. I was thinking I will just go buy it. However, I will need to do the backwards compatibility emulator update from xbox.com because I don't have live. Will doing that update by cd-r have any effect on the iXtreme 1.2 firmware I have? Or is it safe to do and doesn't affect your flashed firmware?