A friend of mine is running an AB character in one of our games and making heavy use of trappings, which for him means using multiples of the same power in some cases. RAW definitely allows for that but in Hero Lab most of the Arcane Powers are listed as Unique. I can fix that for our game, but I wanted to point it out that pretty much none of the powers should be set as unique, allowing all of them to be taken multiple times if a player wishes.