Properly communicating the core mechanic was the thing we were most worried about, because it's pretty unintuitive. You're certainly not the only one who was confused by it. But it's great to hear that you enjoyed the game anyway! :)
It's wasd for movement, e to interact with braziers if you have a torch, spacebar to roll, tab to open chests and your inventory. Use the mouse to drag and drop items into your inventory.
Sorry, we should have mentioned that in the description. ^^"