Thanks. I'll have to try that, once I get the other kinks straightened out.
My test runs have had another problem, though: the AIs lose their freaking minds. The terran comp just mindlessly mines away into eternity, never building anything; the zerg comp starts to take over the base area of the terran, ignoring its own geyser and base; and the protoss comp just continually builds probes and then has them play ring-around-the-rosey at a blank space. It was like insanity mated with bedlam and had an aborted child of failure.
I have each computer opponent set to run the AI trigger "Expansion Custom Level" specific to each respective race. Does anyone know how I can fix their general retardedness? Are there any extra triggers I should add to keep them sane?