Interesting game, with a fun concept. However, I have one suggestion: you should fastly decelerate the player once it's catched by one ring, so that it stops oscillating within like a second. The most difficult thing here is catching the charachter with the mouse while it's oscillating, and it's not fun :D
Moreover, I would also remove the momentum after release: the player does not go exactly into the direction it's pulled from. I think it is because there is a remaining momentum from the arrival direction, but I may be wrong
Art and music are great
Good game though, nice job!