v0.7 released! \o/
There is now instant-death green acid on the floor in the first part. I'd like some input on this, but I think I like it myself so it will probably stay. It also looks awesome. 
I also removed the grating on the floor in the vertical tube. Falling down there also results in death so don't fall down there. 
Some good news for the noobs out there is that I added some extra platforms to jump on in the first part. They should make it slightly easier for those of you not able to gain the speed required to pull off some of the jumps. These new platforms shouldn't change the way more experienced racers do their runs, they are mainly there to help the less skilled guys actually get to the finish line.
The pipes in the vertical tube also got some tweaking. I pulled them out from the wall a bit, rotated them to match up with the curved wall and for realism I added a mechanism for holding the pipes in place. Jumping on these pipes should be slightly easier now.
The main reason people fall down between these pipes however is when they move too fast. So if you find yourself frustrated by these things just calm down and do them one at a time. 
Download, screenshots etc. can be found at my website as usual.