Good little entry! I didn't have too much problem with the invisible platforms, but it would definitely feel more natural if the cube would follow the platform automatically (tip: you can create a tag e.g. "MovingPlatform" and on your character's OnCollisionEnter, if the collider's tag is what you've set for moving platforms, parent it to the platform with transform.parent = [collider's transform]. Put the exact code for OnCollisionExit, but change the parenting part to transform.parent = null or transform.parent = [original parent])
If you've got some spare time, come try and rate my entry! It has 7 endings with a hilarious narrator. Worth checking out!