If you're having a hard time with the last level i'd recommend you to watch this very useful video by Danc3R4ve, short video with clear explanations and great tips, i managed to get a good 00:42.xx run fairly quickly after i watched this :
If you were looking for a guide about every levels, the video in the other guide can be a good way to find out the shortest road to reach the finish line and / or some advanced techniques to be faster overall in a level.
But it's very likely that sometime you'll wonder how this guy is doing such tricks, so if you are really stuck, " Tom Henks " ( nice username ) on youtube did some in-depth video guides for every level if i'm not mistaken.
I didn't had to watch any during my playthrough, i couldn't confirm if every single levels are there, but from the playlist and the few minutes i watched, you should definitely find some good tips on the level you're stuck.
I'm not going to link every video to keep this guide short enough but here's the playlist :
https://www.youtube.com/playlist?list=PLDS-mLWzMEUZ16HYXCWCo...Note that the playlist has other videos like streaming, tournaments, etc, just check out the level's chapter you are stuck, you should find it easily in the playlist.
Feel free to comment if you have any question.