A lot of us devs here are having issues with custom painted Lines. They're all bond to the vanilla scheme by Asobo, which can work great sometimes but many others when designing own schemes can be limitating.
In many situations we would find easier to just redirect the UV Coordinates on our image and like Asobo did with their lines system, combine more UV islands into one painted line.
Is that planned for the future? If not, is there any chance to get something to work this out?