some things to fix:
- in settings I don't know which quality is selected (mark it like when you hover)
- change crosshair when hovering on items/people you can interact with
- pressing escape brings menu but pressing it again doesn't hide it
- scrolling through items is weird (like they appear in order that you collected them but scrolling is in fixed order or something)
- third level note about activating should be on second because you have to activate bomb
- fifth level note should be "cube" not "kube" and "can" instead of "kan"
Also have this video
In the video you can see:
- after interaction you can move (WASD) and only after hovering at the same object that initiated text it can be closed
- after interaction you can move your camera while having your mouse button pressed
- after interaction you can press ESC and RESUME and you can move around freely with text on screen
- contraction and expansion are calculated wrongly (in a way that balls you throw bounce when they should work)
- pressure plate works weird (but I don't know how would I make it through if it didn't)
If all your levels are as short as those in demo then I don't agree about making more checkpoints, I think it's fine as is.
I really like your game, it has some potential for placing it among such games as portal and the witness (you know, the big boys games).