I've just pushed up an update which:
* Greatly improves the flow of the Cave level, getting rid of nearly all of the track jerkiness
* Improves the speed of the house level to make it more consistent and less vomit inducing
* Improves overall performance
* Improves head tracking, so if you stand/sit, change position it will put you in a virtualized seating position that feels more natural
* Resolves the issue where you sometimes wouldn't complete the jumps!!
I have a new world (water world) that I'll be releasing real soon, hopefully this week; but I wanted to prioritize these fixes first.
Please note: Supersampling above 1.2 will almost certainly lead to a very jerky experience, irrespective of your hardware. For time being, I'm only officially supporting the default value of 1.0, as user's who are using out the box values are reporting a good experience.
As always, check the tracker to see what I'm up to, and comment here if you experience any weirdness. https://trello.com/b/vUFkeyC0/vr-coaster-extreme-bugs-issues