The UV map adjustment of curve road.
I mainly use Split Tools by TIG and Thrupaint of Fredo Tools by Fredo6.
The quadface construction of surface is key point. So quadface UV control of surface about Sketchup model is importance to Thrupaint plugin.
Sketchup 2018 & Split tools & Fredo tools
The choice of UV editor pattern about Thrupaint which is belong to Fredo Tools.