Yes we found 2 bugs.
1) Although there were only 30 grid slot at South City, if enough people join at once it was possible to get 32 players to join, in which case two of them were in the centre of the map (not on track). This is the easy one and I've now fixed it.
2) With so many people joining Victor's photo host at once, eventually a bad bug shows up where "a player is connecting" and that player never joins or times out, so everyone gets stuck. I'm on the case trying to fix this for another heavy test this evening. If this is fixed and survives extreme testing I will be confident that all is running smoothly and we'll be safe for patch X tomorrow.
But that's enough talk, I'll get back to fixing that "host killer".