Alright so, multiple things here.
I love the aesthetic and the overworld, somehow it makes me thinks of Krusty's Fun House (I know, really obscure reference, but still). The music is good and the little sound effects are nice too.
Now... In the web version, I can't get past the story telling part, the dialogue doesn't start for some reasons. Also, using Space for a confirmation in the main menu instead of Return seem wrong. I'm sure a lot of people couldn't get pass that.
For the puzzle, I'm not sure I understood how the wood plank thing worked... It seems like you can only go one way, but there's no visual indicator to tell you what that one way is, so it just makes it frustrating to test every single plank.
For the stretch mechanic, I feel like it has a lot of possibilities, but I feel like the implementation is a little clunky. I got stuck a couple of time, and I didn't understand why, and then I could jump of again, still not knowing why. It feels like the stretching and the jumping should be 2 differents mechanics and the stretching should have very specific rule (like can only stretch when not moving, no moving while stretching, these kind of stuff).
All in all, I think it's a nice visually polished game, but I think the mechanic need a little bit more rework to be intuitive to the player. Keep it up!