I already own X3:TC, purchased either through Gamersgate or Impulse (Can't remember which) long ago, and it's registered. I am thinking about buying the X3 "Terran War Pack" from Steam, which includes X3:TC and AP.
I might like to have two copies of X3:TC on my machine, one still running my old X3 campaign, and this new purchase running my new AP playthrough. (I have saved game bug that's ongoing with my old game and shows it as modded. I don't want to screw it up by trying to run it with a new, "clean", X3:TC!

My questions are:
1) If I purchase the pack, I assume it will install a fresh install of X3:TC and AP in the Steam directory and will leave my original X3:TC install alone, yes?
2) If I purchase the pack, will it require me to register again to activate the pack and will that do anything funky with my forum membership stuffs? (I don't want to cause an account problem by having registered two different serials for X3:TC and a new one for AP.) (I don't know if my old serial, since it's a non-steam version, might be able to be used to activate a Steam version or not.)
3) I'm tired of fighting the Steam war and I suppose I will welcome our new robot masters... But, more than that, since I don't want the new game Egosoft put out, I'm going to fulfill my pledge of "donating" anyway by buying a bundled pack, just to show support for a company that has a product I do enjoy. (Don't count on that happening again if Egosoft comes out with X4:DonkeyRevolutionPonyIsland!

Thanks in advance for your always awesome assistance, TS people!