Yes Tony print 2 of everything, put one copy of chatlogs, in with the original docs & one in with the copies. There must be 2 of everything.
You need to package them properly, or they may charge you extra.
I put ours in 2 plastic folders, as mentioned above, then both in a big jiffy bag, then in one of those tough postal bags.

Screenshots of chatlog dates are good, that's all we submitted. They're not looking for all the actual chats.