zandatf/custom/customfolder/materials
this one, also note that those vtf's must be specifically named
eg in models -> hand_lightwarp.vtf; mirv_lightwarp.vtf; weapon_lightwarp.vtf
player/pyro -> pyro_lightwarp
now i don't know if vmt's are needed, but those are easily generated in vtfedit, just be careful with specifying the destination in them