BG crash

I've played through BG1 using the BG triligy patch, but since it was incompatible with the romance patch I did a full re-install of BG2 with TOB and the edwin romance patch for SOA and TOB, then copied my savegames across. I have no idea why, but when I try to leave waukeen's promenade for the first time (right after the circus) the game crashes, without even auto-saving.

This means it's crashing either at the map screen or when trying to read some 'end of chapter' story to you. Any ideas?