The elevator needs to pause for a few seconds at the top and bottom. This will make it less frustrating for people.
Also, Z is a very odd key to use. Most people use both hands when playing. If you are going for 1 handed play, I would suggest making Z or Space to use sword. Also you will want to allow players to change key layout, but that will obviously complicate things.
It's an appealing start. I like the graphics. Like I've seen many places, make it easy, especially the tutorial. On that note, I would suggest a popup when you get to the lift hinting to go explore to the left.