We finally decoded what Microsoft demands (but not clearly) to be Vista compliant. Microstudio 4.006 has the latest changes. In essence, Windows Vista will NOT allow you to have any working/editable files (such as a Playlist in Microstudio) in the C:\Program Files\... path. All editable files must now be in C:\Documents and Settings\... path. When you install 4.006, we will automatically MOVE all your working/editable files to the correct path.
It's not as easy to find files related to any MTU or any other vendor's Application programs, such as Microstudio, Hoster, Vogone, etc. However, look at it on the positive side... you'll be Vista Compatible.