Digging this game and the lighthearted feel it has. The music is spot on and is helpful to get the player in a flow state where they're stealthing around, picking or dropping objects, and just exploring the game area. Aside from the controls breaking a bit that flow state, I think you've got something on your hands here and nailed your goal in the Adventurer track: the game is fun and well polished.
I won't beat around the bush too much with the controls since everyone has already said something. I did find two other issues. 1) Dropping items doesn't seem to always work, I have to hit the numbered keys multiple times until the item actually drops because a single press doesn't work. 2) I got stuck on the wooden platform leading into the castle, around the side. I seemed to have fallen into a hole that I couldn't get out of. That stopped my playthrough then after spending some time getting comfortable with the game's controls and rules.
Looking forward to further updates on this project! Do you plan on adding gamepad support? That would be amazing!