Hey Manatee,
I am actually looking for the same answer. What I have found so far is a bit disappointing.
Only some leaderboard functions are exposed to blueprints, you can only write to leaderboard, read and flush. Compare to what Playfab plugin provides, this is it not enough to make a solid leaderboard for Steam. The other functions are available in C++ class, like get leaderboard for friends or around player…
So to add up to your question, can someone show us how to expose these functions to Blueprint (I know you can do it as I had to expose getSteamTicket and it worked, I had to follow a step by step tutorial).
Thanks.