So you're after a trigger that trips when the group moves onto it, with end 2 if there are less than 8 units and end 3 if there are more? I'd use two triggers:
Trigger 1Radius:
covering area to get back toCondition: Group Leader Present
Type: end 2
Condition field: this and (west countside units
group < 8 )
Trigger 2Radius:
covering area to get back toCondition: Group Leader Present
Type: end 3
Condition field: this and (west countside units
group >= 8 )
Group those triggers with your group (F2 and drag a blue line from the trigger to your group leader) and you'll be able to get the
Group Leader present option in the condition box
[size=0.5] [Edit] Would you believe that putting an 8 too close to a ) results in a
? ;D[/edit] [/size]