I have played sometimes the game and I have some questions,
1) Can the action card heavy weapons be played by the defender
or only by the active player?
By either player.
2)Can the fog of war cancel another card fog of war?
3) When the russian plays uranus card that reduces the number
of the cards during the draw card step, does it includes the
five basic cards or only the extra cards (relating to the
locations you control)?
It reduces the total, which is pretty much the same thing as saying it reduces the five basic cards. If Propaganda War card is played, he doesn't get cards for the locations, but he still gets the basic five, unless the Uranus card is in effect, in which case he'd only get 3.
These responses are based on my understanding of the game, and how I've been playing it.