For the small development team that they are, multiplayer is probably the hardest thing to create and i think that they said that they don't intend on adding a multiplayer very soon.
Instead of when you die and you cant play the save anymore, it should be when you die, it would take you back to the last time you saved.
Some of the items can be picked up and are still forzen, just thought id mention it.
You should add in signs
Bug, http://imgur.com/a/LNNeP