What a great classic game! 

I really find the orbs coming down as you "free" them as a really great twist and a good interpretation of the Jam's mechanic!

The game has great game feel and really feels impactful with the sounds effects and music. 

I also found the different levels and orbs placement really interesting - the final level being a skull with the orbs being eyes was a great touch!

Just some quick ideas:

• I feel like you should punish the player by not picking up the orb, or rewarding him if he does pick it up. After I learned you can shoot the orb to finish the level I just shot all (I know you don't get score if you shoot them but I feel like losing life or something could work better). I would even go so far as to remove the ability to shoot the orbs and focusing on the "catching" part.
• Collision detection is sometimes a bit off on the shots. Very important because I did try to free orbs at times without shooting the orb and had some issues.

Other than that, great game!