Testing Grounds is a basic map with some modular track sections that snap together so you can make your own track layouts. Use the snap to grid option set to 10 meters and the parts will snap together. Hold down shift when rotating to snap the rotation too. Use shift when dragging parts to duplicate them. I have made a track using all the parts and painted AI roads under it for the heck of it. It takes up half the map so you can make your own layout in the other half, or delete my track and go nuts. I may add more parts in the future, but for now this will have to do. If you want to use the parts in your own map, just place the ModularRoads folder into your map. (Please note this was made in sketchup, so if you are using them in your map only use the objects that don't have Low or Col in the filename) Let me know if the map isn't working right, as I have only tested it on my machine.
Has potential to be a really cool way to play with making your own realistic tracks, will say the textures look like they could use some work, but first impressions without downloading are good.
I'm not a texture artist, I just used what I could find. I had another set I was going to use, you can't swap them out if you prefer them. Original Or this? Just replace the two.dds files in the ModularRoads folder with the ones I provided in this post, or make you own better one.