queston on impluse versions

hello guys I just found this game and boy we love it (my 7 year old and me 7 going on 40)
I made the mistake of buying it on impulse now that i know i can buy it direct my question is

will the expansions work if I bought the main game from impluse?

my reasons are i have recently had a problem with impluse and gamersgate working together (HOI3 and HOI3 semper fi)

if I buy the nomads and campaign direct will they install or does impluse change the game so i have to buy the expansions from them?