We need more info to help you. Like:
Chipped or softmodded?
What do you mean by "if I load the xboxdash from avalaunch"?
If it is chipped and you mean your M$ dash is goen when you turn the modchip off, try and put in a XBOX Live! game and coldstart your xbox. Choose to go to live in the game and it will download the M$ dash.
I hope this helps, good luck!
Chancer was just faster