How about this:
QUOTE
What I am trying to do is, whenever a dropship drops uA, and uA(Current Player) is next to a trap (Player 12), uA will be given to player 12, and the trap will be given to the current player. Then when the dropship drops uB, uA will be given back to the current player, and the trap will be given back to player 12. I got only half of it working, when the dropship drops the same unit the second time to toggle it back to normal, everything remains the same, the current player still has the trap and player 12 still has uA.
I guess I read it wrong originally. I thought you were droping two different units at the time I made my post so that uA would be the first and uB would be the second one droped. How about this:
uA for the dropped unit.
land a land only location on the field.
transform a 3x3 location to detect the changes.
C:
Current player brings at least 1 uA to land.
A:
Center location transform on uA owned by Current player.
Preserve trigger.C:
Current player brings exactly 1 uA to transform.
Player 12 brings at least 1 trap to transform.
A:
Give 1 uA at transform owned by Current player to Player 12.
Give 1 trap at transform owned by Player 12 to Current player.
Preserve trigger.
C:
Current player brings exactly 1 uA to transform.
Player 12 brings at least 1 uA to transform.
A:
Give 1 uA at transform owned by Player 12 to Current player.
Give 1 trap at transform owned by Current player to Player 12.
Run AI script "Enter transport" at transform.
Preserve trigger.