I'm sure a lot of people played a lot of MP games of HoI2, but like the OP, mine were always plagued by problems.
Over the course of each multiplayer game, there was always at least 3-4 things that got 'lost' each time the server loaded up the save for the next session, like research not being completed, events not having fired, excess dissent due to a lack of CG (when the player would have obviously put IC into CG).
And you don't know the game is out of sync until someone notices that something is wrong. I had a game over a LAN where, once 1941 hit, the USSR player noticed that none of his divisions had upgraded past 1936, because the server didn't think he'd researched any infantry techs, although they were completed on his machine.