Yep, i means this.Thx.I think he means the tire/tread marks on the dirt. Ketch is correct. Those were done with projectors. If you open up Arad, you'll see little movie projector icons hovering over the roads where you see those marks. If you open up the projector actor properties, you'll see that an alpha tire mark texture is being projected onto the terrain. Experiment a bit with the properties and you'll see how they did it. Or if you want, just copy and paste a few into your map and arrange them however you need them to look.
that texture is already alpha, to change the opacity you need to tweak the texture in a texture program. only i found out that once you rework this texture and project it on the terrain, it gets duplicated and you get like 8 roads parralel to each other, instead of 1.