When you're looking at the Sim Description, click the Uni tab and change the semester number to 1.
That was the first thing I did.
Looks like spawning the sim modder will do it. Let me just check that it doesn't fudge anything it shouldn't.
Edit: Yay! The sim modder had an option to re-set. She now has 4 want slots, 3 fear slots ad one lock. And just to compensate for my idiocy I gave her an extra fear slot while I was at it (but at least I know how to get rid of that now). From what I can see, memories are intact, and she still paints §1900 masterpieces.