I've been messing around with the SC:BW campaign editor lately, and somehow the triggers still baffle me. I was wondering if a seasoned map editor could help me with these problems:

I want to know how to set a trigger for turret defense maps - for example how do I create units at a certain point on the map and send them on strategic attack missions? I've tried many triggers and it seems they would work, but most are very buggy.

I also want to know if I can make the user's race selectable, but still use custom units. e.g can I keep a gateway, barracks, and hatchery all at the same spot somehow? or does 'user selectable' not apply to custom units?

Any help would be greatly appreciated.

p.s does anyone have a copy of the old evolution maps? I'd like to play them again sometime