Hi :)
I just want to let you know about the current status of the game and show you some more pictures.
So far I finished the graphics for more than 50 of the 60 tracks. Have a look:
A medium sized track:

Another medium sized track (some rocks will be added):

And finally the new terrain type on a small test track:

Integrating those tracks will take some time and there are some more things to work on, for example controller support.
I will regularly report on the current status, always letting you know how far everything is. :)
Thanks for reading and have a great time!