CROmartin in regards to your prev question, I think the way i got round it was to give each player an id (instead of using MyActorNr)...
4 players > on join > id = 1, 2, 3, 4
Add a 'room variable' called 'availableSlot'
player 1 leaves > availableSlot = player1.id
player 5 joins > player5.id = availableSlot (player 5s id becomes 1, to replace the player that just left).
Hopefully this makes sense, might be a better way to do it with arrays