Thought you were on holiday for a whileSepang from GP4 has a totally weird road mesh. I could not add road bumps to it.
For Melbourne, why not, but I would need permissions from the team you mentionned
version two the better way: when the tracks are using the reiza commonmaps.mas (check their scn files if the mas is linked there - MASFile=CommonMaps.MAS) you can use the sce standard textures...
open the tdf files of the tracks where you have problems with a text editor and change all entries with
skidhard to skiddry and racegroove to groovedry and save it