Updated my dungeon door so thought I would post the progress for some feedback.
Before:
After:
And here is as animated GIF, actually my first ever animated GIF ^,^
The speed is about the same as in game.
I could add more frames but I don't want it to take long to go between rooms anyway so probably won't add more...
I'm loving this improvement. My main criticism for the main screenshot is that everything looks good, but slightly bland. This takes a door that is good and makes it much more interesting and lively. I think your main character and this door are the pieces that have the most spark of them all so far.
For your backgrounds, I'd make the dark bricks slightly less black and make tiles to show that the front bricks are casting shadows on the back ones to give the setting more depth and at the same time, connect them so that they are more obviously part of the same scene. Right now, the door is supposedly resting up against a wall that is much, much darker than it. It makes the door look like it's floating. I think your front bricks look too "mannered". Add something to break up the repetition. You've done some stuff so far to help this, but take it a step or two further.
I like the little items a lot. The switch needs a little work.
And the ladder and the treasure box are, in my opinion, the worst parts of this. The ladder looks flat and the box looks like you haven't spent much time on it.
This is really promising, so I hope you keep posting updates