Mod question + more questions

[darkwolfdemon]

I played the game awhile ago and stopped playing while ago. One question is what does the secondary objectives serve to do?
I remember the first mission where you get on a hill, order an attack and that's it; while the secondary objective you walk to the other end of the island to blow something up and walk all the way back.

Also the main reason I bought this game is because in a previous game of the series I was able to make huge battles with hundreds and sometimes a thousand units (or close) in tanks, choppers, and other fighting each other. I was terribly disappointed when this game's mission editor had a max number of 64 units and otherwise it would just not work. Is there a mod to let me able to have a huge number or unlimited number of units in the mission editor?

Thanks