Re: How does ground combat work, exactly?
 

Have a few fanatic-piloted troops, then have a lot more droppods. 1 component gives the bonuses to the entire stack.

Re: How does ground combat work, exactly?
 

No. No special damage types apply. Pretty sure that every type of weapon you can put on troops acts like a ground cannon... Nothing fancy at all. Note that emissive abilities do not work on troops.

Re: How does ground combat work, exactly?
 

*AND* because special damages are ignored, if you're smart and using stock game (the two are almost always mutually exclusive), be sure to use shield depleters on all your troops, as they have the highest dmg-per-kT rating of all weapons, and are thus the most powerful.

.....and armor regeneration most certainly doesn't work, as units don't take partial damage, so the only reason to use armor is that it gives the troop extra resistance - but at the high attack values of GC, that is mostly irrelevant, unless you're using a massive troop. Shield regeneration I am uncertain of. Wouldn't count on it.

Also, if you're planning to make a mod with altered GC, I think you might find the Capship GC interesting, or perhaps the GCM (Ground Combat Mod)'s GC, as that is where I got my inspiration, though the two mods are by far not the same.....