Omegamatic

I understand, would've been classy if it was a real thing tho.. 

You mean queues? Without external program or special mouse, you can't, really. RA2 engine doesn't have a shift-click equivalent to that of Age of Empires or newer C&C (?)

So the only way to play with "Shift + Left Click to Add multiple build orders" and "Shift + Right Click to Remove multiple build orders" is with a special mouse or external program? if so, which mouse/software is it?  

I'm asking because user "Foxtrot1_1" mentioned it is an actual hotkey in his comment on this thread.

can someone please explain how adding multiple build orders is expressed in the game as opposed to removing multiple build orders?

I don't get it.

Is it possible to play the campaign on 60fps?