Hey guys i got with the Idea and needing i thought of making an improwment to my game and taking the advice so what is that major one? i need a huge flat terrain with 5 varions of circles (like on big and 4 smaller inside that can be made into alot variations like circle 1 than circle 1 with 2 conected and so on (IT IS POSSIBLE WITH SKETCHUP it could be or rigbody WITH .COO or skinmesh 
also i need it to be big about 5-10k radius (draw circle for this) i would make for myslef but i'm low tallent and skills also i need 2-4 variations of barrel and 2-4 variations of cones 
and different 2-4 different metal or wood walls
and some cool turns like S form ot M form? COULD somone be so generous and make them for me? i will try to make for myself also and here is photo what have i done for so far :
also i need it to be big about 5-10k radius (draw circle for this) i would make for myslef but i'm low tallent and skills also i need 2-4 variations of barrel and 2-4 variations of cones and different 2-4 different metal or wood walls and some cool turns like S form ot M form? COULD somone be so generous and make them for me? i will try to make for myself also
and here is photo what have i done for so far :