k, I am confused by just reading your post.
We are going to start all over.
First off, delete everything that you previously installed regarding xbmc....clean up the e:/ drive to things you use and know.
now you can put XBMC in c:/, e:/ or f:/ doesnt matter, I myself put it in e:/
in e:/ I have a folder called "apps" where all of my applicaations are such as dvd2xbox, Xtools and XBMC....I use XBMC as a dash, but I sitll keep it in my apps folder.
So basically create a folder called XBMC where ever you want.
Now get an official release of XBMC, compiled and not source code.
Now this build should contain many folders some being (system, python, mplayer, media, language, docs, credits, skin, visualisation, screensavers) then there should also be a default.xbe, xboxmediacenter.xml, keymap.xml, kai-vectors.xml and filezilla.xml.
Note: newer builds of XBMC will not have the mplayer folder, as it has been integrated into the code and there is no longer any reason to have a mplayer.dll
so once you get the "build" just ftp it to the XBMC folder on whatever drive you want.
now using whatever dash you have as a default, do a search through the files on your xbox and go into the XBMC files and then click on the default.xbe....and wolla it will run.....
Once you get this running, then do some reading on how to set XBMC up as your default dashboard....but first get to at least this point....if it doesnt work, then you dont have a good build of XBMC....and pleasedont ask where to get a "good" build, no one will tell you here.....
hope this helps
j_guzzler