I have just finished trying to duplicate your bug without any success.
I tried opening a map window and closing it without a change - no freeze. I make a small change of any kind - no prob; window closes and "Map" appears in the column. Click it again, the window reopens, hit clear, window closes, "Map" disappears.
I also tried this with multiple instruments and no issues there either.
All I can think of is: Do you have any Instruments defined in OMS and subscribed to in SVP, or are you opening a Transpose window on a "blank" instrument line?
Before you can do pretty much anything with an instrument in SVP, you have to first create and define it in your OMS Studio Setup which SVP then subscribes to.
The Studio Setup is NOT stored in SVP but rather in the OMS Studio Setup Document.
If that Document is nonexistent or screwed up somehow, SVP might freeze looking for something it can't find.
Any Transpose Maps you create are stored separately but they still have to reference the original Instrument.
If not any of that, then somethings gone sideways, probably in the Studio Setup although who knows? Could be SVP too.
THEN, you're in trash everything Opcode and reinstall from scratch territory.
Again, the type 2 error pretty much always requires a restart. Even if you're able to get SVP to quit without the entire system crashing, OMS doesn't quit and launching SVP again makes the system try to launch another instance of OMS and you just can't do that.