A lot of interesting ideas here so I'll definitely keep an eye out for further updates. Definitely has a lot of that early build jank though. 1.5 GB is pretty wild for a 0.01 build.
Not a fan of the unlock / peek / knock menu controls. Scrolling to select feels pretty cumbersome. Why not use WASD? There's only 3 options so I think giving them dedicated buttons in the action hints would be better. I also don't like how peeking always puts you into a crouch position afterwards. I'd rather it return the player to the previous position .
Getting a game over broke (bordered) fullscreen mode for me but thankfully it can be quickly fixed by re-applying it in the settings menu.
Movement in the vents is really finnicky. It's very easy to get stuck on walls if the camera isn't angled correctly.
I think the low-res pixel art clashes pretty hard with the environment currently. I'm not familiar enough with 3D to advise you how to improve it though :(