No errors in the console in FireFox. Just get the "A script on this page is slowing down the browser..." notification. On multiple refreshes it loaded the menu screen but with no images or fonts.
Downloadable works fantastically.
After getting to the room where you have to jump, switch blocks and dash multiple times, I understand the controller recommendation. That took quite a lot of attempts on keyboard but is do-able.
This is really nicely polished. Really intriguing story and outside of the jump/switch/dash room movement and control is nicely crisp.
Good luck in the jam!