Lol nice for a game, Although there is a lot of things wrong with this, oh and i used to make games with GameMaker Pro v10 i think, It was back in the day with YoYo games and a bunch of people, But anyways..
1. The sprites are meh.
2. The Char. animations are a bit poopy
3. Character is too big for the world.
4. Buttons and GUI sprites need some more textures.
5. More items.
That is just a list of things that i suggest you fix/put in