Can do it, yes. I have a 536 with all 4 zones created. You can't pick up all 4 zones at the same time due to where they are located. (ie: you can't hear an Ottawa transmitter in Windsor).
As far as TGs are concerned again yes, you can load in all the TGs for each zone into that zone. But again, since the TGs are duplicated with different users in each zone you cannot hear a zone 3 TG user in Zone 1 even though the TG is the same number.