yea 0 and 1 is for north and south
If you need some evidence that a selection hack (selecting more then 12 units) exists, i belive your are talking about a multicommand, there is one in zeroV2.3.dll (damnation hack) it alows you to send a command to all your units or buildings of the same type by selecting one of them and telling it what to do (like move to this location, attack to here, patroll to here, build a marine, select a rally point ect)