Quicktime for XP

I have the Rosetta Stone. RS uses quicktime. It is the only reason I
have quicktime on my machine. It works fine on my XP machine until it
tries to display a moving image. I get a display error and it exits.
I have tried changing the compatibility mode and no setting stops the
error.

The same software runs fine on my XP laptop. I have installed all the
current updates.

Suggestions?
.