then you forgot something. edit poly modifier -> face selection mode (the square) -> selecting faces -> set id (1 or 2 for two materials/textures) -> unwarp uvw modifier -> flatten mapping -> still in face selection mode -> select / drag around etc.
then you forgot something. edit poly modifier -> face selection mode (the square) -> selecting faces -> set id (1 or 2 for two materials/textures) -> unwarp uvw modifier -> flatten mapping -> still in face selection mode -> select / drag around etc.