hi,
today I had that error 21 - problem as well.
I tried to put ava as default dash, but that didn't work, I think because of my older bios.
So I decided to go back to evolution X in a new version.
Everything worked except the msdashboard didn't.
The Problem was, that in the evox.ini the path was for msxboxdash and not xboxdash so I fixed it and after that I had the same problem with error 21 ("call tchnical support...")
For me the problem was solved after I deleted the folders "xboxdasdata 10027100","fonts" and "xodash" out of my xbox c: drive.
Than I put in my original Splinter Cell and downloaded the live files one more time. After a reboot I am now able to load the msdash out of the evox menu. and there is the live menu in it now.
i'm not sure, maybe it was simply great luck, but maybe it works for you too,
Greetz Belus
...and sorry for my english...