I have been testing an alpha system for games making. it has a waypoint following texture adding for roads that's very good.
I cant place a video of it here I don't think that's right tbh imo, but the system could possible be a great way to add roads to the editor?.
how it works is, you place waypoints for the road to follow. then with some tweaks you can change the mapped out area of waypoints to better suit you. then by adding textures to the marked out areas you have a road system made, now in this software it comes with a smooth over brush to get the roadway to stick better to the terrain, uphill and such. also it has an option to cut into terrain so you can make roads with cliffs either side.
this is done using Lua scripting I think but am unsure as I know nothing of it and scripting in general, but I do know they use Lua for the scripting of stuff.
have fun stay safe
hood