Sorry for the uber post revival, but im curious about the question above that was asked (and never answered).
I am about to tackle that exact same situation myself and was wondering how it was done. I assume with some sort of trigger, and an output?
Also is it possible to turn lights off every say 5 minutes, leave them off for 30seconds and thrn them back on again? I assume a logic entitiy would be involved and maybe a counter?
Only been using Hammer for 3 days now but already 65% of the way thru converting an old HL1 map to HL2DM

loving it so far.. VERY helpful forums!!