after having played a few games, i found some that have a unit spawn, attack, and disapear in nearly an instant, i was wondering how to do that

Few games of what?

Best guess I can give with so little info is that the mapmaker triggered a unit to spawn, used an Order action to make it attack, waited a set number of milliseconds (to give the unit time to attack), and then used Remove Unit at Location.

I've tried that. for one there are hyper triggers pressent, meaning no wait triggers. second the units attacking are spawning over and over, the second one attacks and dies before the first ones death animation is even complete

You have 3 pretty simple options here:
Create the units and let them attack (with and without order to attack)
Move the units and let them attack (with and without order to attack)
Open up the map.

I don't understand your problem. It sounds like you got them to attack quickly.

You should really explain it a little better. We have no idea what's going on or what effect exactly you're trying to achieve.
My guess is you wonder how they make a unit attack super fast by constantly respawning. You'd do that by always centering a location on your unit and killing/recreating and ordering to patrol it after a certain amount of trigger loops (you'd have to test how long your unit needs to shoot).

Post has been edited 1 time(s), last time on Mar 14 2010, 8:26 am by NudeRaider. Reason: added a vital part

Usually you spawn a unit, order it to attack via AI, then remove it. You usually have to tell them to attack to a location other than itself.

use patrol order for around 400ms and then remove the unit. It should attack real fast.