2d game environment

I have been making a 2d side scroller game similar to the ios game - bike race.
I have currently made the track simply with cubes. However I want to create a proper track similar to the above mentioned game( proper loops, curves, ramps).

Bike Race
https://play.google.com/store/apps/details?id=com.topfreegames.bikeracefreeworld&hl=en

Can someone point me to an asset with which it is possible to make such tracks.

Also using which asset can we make environments like in ski safari/ stick stunt biker 2?

In 2D use RageSpline/Rage Tools/RageTools Pro (Freakow) for the Asset Store and in 3D use MegaShapes (Chris West).