I haven't encountered any of the game-breaking bugs. What I have encountered are:
1. I can't get two of my sims in the same household ride a fair ride with other sims. Only one of my played ones can ride with someone at a time.
2. My sims also can't claim a locker. That may be because I had them claim them in another save, and decided to move them to another save for a fresh start. I had them drop out of school and re-enroll and it didn'tfix anything. I'm not too bothered by that because there isn't much gameplay involving lockers anyway. It's not like they store books in them or have backpacks.