Or you could try somethin else.
Create 4 Triggers ( for the 4 groups), make them all the same radius.
Now you link every trigger to one group, and in the activation field of the triggers, you use:
Trigger 1: wp1=1
Trigger 2: wp2=2
Trigger 3: wp3=3
Trigger 4: wp4=4
Now create another trigger, and in its condition fiel you write :
wp1==1 and wp2==2 and wp3==3 and wp4==4
Thats how I always do it.