Not sure if you're aware, but you can download the rules for all the '4X games from the GMT site and there are Vassal mods for them all.
Thanks.
I'm not a fan of vassal myself. In all honesty, for me a board game holds something very specific that you can't get from a computer game...tangible feeling. The idea of playing a board game on a computer doesn't fill me with glee. I tried to love Conflict of Heroes by Matrix Games but it just didn't click.
For me, board gaming is about getting the game out. The setup. Physically moving units. Physically checking LoS. Physically rolling dice. It's about the often quaint map graphics. It's about picking up the manual to re-read a rule.
That's board gaming. Playing them on PC is as mental to me as clipping corners on chits is to BH.
Having said that, I do have Heroes of Stalingrad which I thought captured the essence of boardgaming whilst not having all those tangible "feel" aspects.