Kaedrins Pack + Coop Gaming

Okay, im so very sorry if this question is hilarious or easy to answer, but i dont get it right now for the moment:
Is this Pack (when both users have it installed) coop playable or not? im really not quite sure and i am very sorry if there is a faq or something where i could have read this...

this pack seems very awesome and i just want to play it with a friend of mine...oh and: if it is coop playable, which version do i install? the singleplayer version? or anything else?

big thx in regards
phantagor

It works fine but every player has to have the same version.

The single player download is the one you need.

Ah thx for the answer, but i already found out^^...but still, thx

and big thx for the lots of work you've done with this pack...its quite awesome! (cant what to see more coming^^)