1. No idea when D2D patch will be out, but IIRC 1.1 was out LATER than the boxed version. I'd go on that.
2. To answer that question accurately we need your system specs (sounds just like the n00b helpdesk assistants at Dell at my ISP). I'd say if you had no problem till now you're fine. Only later on you may have Huge city battles which are a burn on the GPU. Anyway if you're playing your game 'right' you'll never have to do a city battle.
3. I don't think so. Perhaps marginally by 3-4%.
4. M campaign, VH battles. Have played a lot og VH/VH but it's silly how dumb it gets sometime. I know it's called Total WAR but hell it's not called annihilate my sorry butt, and that's what the AI begs for on VH/VH. Glad to oblige though. :)
5. 1.2 will probably NOT be savegame compatible, no official word on that IIRC, but that's how it always went.
One thing I'd recommend is installing Carl's PureFixer, it addresses a lot of the bugs currently in the game. It's a compilation of fixes by various members of the community. It's REALLY worth the install.
I did'nt play since December because of the bugs but now, man, this game ROCKS.
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