What I liked :
- Fantastic puzzle mechanic (already seen, but not used in this clever way)
- Level design is progressive
- Head-scratching puzzles
What could be improved:
- Using the mouse. I would prefer something like using space an action key to give the action, then just space to retrieve it.
- Don't see easily when I can take an action, particle-effect is too long to warm and too subtle. I think you could simply change the frame of the action with alternate colour, and add a subtle SFX for entering/leaving an object zone.
- Bug: Sometime action can't be taken/set even with the particle effect indicating you that you can.
Hope it helps.
Overall, that's a great game.