Can you adjust the attacking power of units, similar to adjusting hitpoints?

In triggers? No.
But in unit proporties ofc.

If you want In-Game ajustments then the closest thing you can do is give the unit to a player with upgadres for that unit, Or change it to a hero, Or force upgrades.

Post has been edited 1 time(s), last time on Jan 27 2009, 6:05 pm by Pigy_G.

I'd like to do this while playing so probably i can only use triggers. Ok how do you force upgrades?

You can't.

Well, you can make the game unable to continue until they upgrade, I.e you center their screen at the upgrade place until they upgrade. And give all their units to neutral.

Wait a second...

http://www.staredit.net/topic/5332/

I can't believe I forgot about that! It tells you how to make the computer upgrade weapons and armor on demand. It only goes to level 3, unfortunately, and might have a bunch of side-effects, but it would be useful anyway.