Anyone know how to fix?
I would suggest that you try reinstalling.
If you remove the Studio Artist application file from the main Studio Artist folder, then it can't find the presets. Same thing if you remove the Preset folder from the main Studio Artist folder.
We've also run into a few windows users that seem to have software installed on their windows computer that automatically removes what it considers to be 'unnecessary' files. That could be a potential source of the Preset folder vanishing. A damaged file system on a hard disk could be another.