Just to echo Jake's sentiment:
This looks great, characters are great, environments are intriguing. But, yeah, I ran into a whole bunch of mapping errors, teleports leading to wrong areas, game breaking bugs - including the "cannot read property 'contructor' of null".
I don't think any bugs I found are major problems though, and I'd love to play this again when the kinks are ironed out.
Worth playing just to see the great artwork hung on the walls!