I've reverted to SP02, and restored my repository from the backup I took before I installed SP03. Now I'm patiently waiting for SP03 PL03.
I have some models I'm going to leave alone until PL03 arrives, as they've been updated to SP03 already.
Luckily most of the models I'm working on now are either uncomplicated, so they revert to SP02 easily, or they date back to before I installed SP03. I wish I'd reverted to SP02 as soon as I started getting problems. Not to self ...