I really love the idea of a sandbox-marblegame. Unfortunatly the physics seems a bit weird. the marble got stuck or bounced really weird often times. but thats something that just needs some tweaks and adjustments ;)
would have been interesting to further deepen the rewind-mechanic into the gameplay. for example rewind only reverses forces on the marble and you can change the track while rewinding? (physics wouldn't like that either but i'm just dreaming ^^).
I had the problem that i grabbed the remote randomly very often. maybe the remote functionality could also be mapped to the left controller?