startObjectTween should unregister after the delay value has ended. I haven't gotten round to checking out the .ved you uploaded yet, so I have no idea what it is you are doing...
I don't think need to create a scene object to do mouse scrolling. With lua I believe you could just get current scroll position & then check the current mouse position against 4 values based on game resolution value.
I can more or less think of how it could be scripted but I'm a bit busy at the minute...