Have you tried checking whether the VST folder config in Music Maker is still pointing to the right location? Just set and rescan the folder. That should do the trick. Not sure what version of Music Maker you're using. In version 15, you'd just have to go into the program settings/path settings and use the relevant button to locate and set your VST plug-in directory. In the MM 14 Producer Edition it's a little more tricky. You'll have to open the MIDI Editor (e.g. by dropping a software instrument into one of the tracks) and open the "Instr." drop-down list, go to "Software instruments" => "VST plug-in path". That will let you browse for the VST folder on your hard drive. After that is done, you can simply close down the MIDI Editor again and delete the object. Open the mixer window and you should find GSnap in the VST plug-in slots again (if it was in fact in the scanned directory).