Try setting the trigger to use a specific location that you draw using the "Location" layer. This location should be near a resource spot. Do not "run the AI script at Anywhere", you must have a location (e.g. Location1, etc where it is a location you make.
Use the Insane Campaign AI or a Custom AI because other campaign AI's need to start on unequal footing to work right.
All you have to do is go into the location layer and make a small square in the middle of their base. This is location 0. The choose ALWAYS - RUN AI - ZERG CUSTOM LEVEL(only if they are zergs) - AT LOCATION 0
When you use Custom AIs in games where the starting condition are imbalanced, the Custom AIs do not attack or build because as they view the condition as not being able to win. You have to use Insane AI for them to attack you and build, when using the AIs in Melee games, the computers sees a clear disadvantage to them so they do not even bother to built/expand, this does not happen all the time but it does happen. The best AI to use is Insane AI. The campaign AIs only build the mimium requirements to advance the tech tree and collect resources very slowly (4 drones max, only one hatchery, while Insane AIs build 2, Insane human AIs built more than 3 unit producing buildings each, like 3 factories, stargates, etc.)
Try "set ally statis" and say "P1 to enemy" then make a new one and run the ai to "run ai script" "send all unit on strutegic suiside missions" then one morn new and select the apropriet dificulty you want. if that dosent work make sure that the computer has a land passage to your base cuz they wont come after you if thay cant get to you by land (atleast thay wont for me). it sounds like a lot to get the computer to kill you but it has worked for me on all of the maps i have made (5).
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory
I will be AFK for a couple of days you guys hold down the fort while I am gone. I will be checking in on my phone but that will severly limit me. Be back saturday!