This felt really polished and filled out for a game jam! Well done!
Feedback:
1. I liked the personality of The Overseer, it added to the tone of the game. Well done to whoever wrote and whoever voiced that. Voice acting can be really hard. The lines were well written and well performed.
2. I liked the simple mechanics of making yourself bigger and smaller, it was a good decision to have the size affect the weight & speed of the character.
3. Some of the puzzles where you had to make yourself small to run through a door before it closed were cutting it very close! In the first one, I had to run backwards from the button, as I didn't have time to turn my mouse around to point in the right direction before the door closed (even when holding shift to sprint). Later on, I started Jumping to try to increase my speed for these kinds of puzzles. I feel that when you are introducing this mechanic, you don't have to make it so hard to complete. You can always ramp up the difficulty later on.
4. (this is linked to 3.) If you ramp up the difficulty of a puzzle by tuning timing, you increase the 'twitch skills' required to complete the puzzle, this may make some players think that their solution to the puzzle is wrong, when it's really just their timing that's off. Timing can be a useful puzzle mechanic, but I would make sure that the correct solution still allows for the player to complete the puzzle reasonably comfortably.
5. The final puzzle with the moving platform where you had to increase and decrease your size to get underneath the beams in time was genius.
6. This was a really rewarding game to play. If you were to continue working on this game, I can really see all the mechanics and mini-puzzles created so far combining into some great game-play. Well done!