I really like the sound, graphics, and mood. Cool idea having the riddle to answer, but it conflicts with your main mechanic of the dying torch. A riddle should allow time to think, but you're racing to get to the end. It would be cool if there were ways to rekindle the torch so that you're not just hoping to beat the clock -- in fact, when I saw the candles, my initial thought was to stand over them and let the torch recharge (it didn't work). Walls looked a little too similar to the walkable tiles to me, and I tried to walk into the walls a few times before realizing they were walls. The camera-switching between rooms through me off a little and was a bit dizzying because it was a fast slide -- I think it either has to be a slow slide or an instantaneous switch.
I made it to the third room, in which I died to all the skeletons, and I didn't want to play through everything again because I already knew that I could. I already had fought the skeletons and answered the riddles and figured out the codes, why would I want to do it again to get to the same spot? If you had checkpoints at each room, that would make it a lot easier for me to finish the game.
In the secret code made of tiles on the floor, I think you should make the tiles a lot more obvious -- different colors maybe, or at least very obvious designs in them. The X and I were fine, but the other two I couldn't really tell apart, and I was lucky to get the code at all.
Lastly, I agree with all other comments above about combat.
Summary: good mood, smart ideas, some adjustments could lead to a fun short game that feels rewarding to play -- you're not far off the mark from that! Great job -- I really do think you're close to a more flushed out experience.