There seems to be no official rules set for team play for Terrace. Four player abstracts that I have intrigue me (Blokus and Ploy) and it seems to me that Terrace could also work as a team game.
Wouldn't it work if adjacent players (blue and White, red and black) were partners in the contest? Teammates would want to move their "T" to the same opposite Level One square; the rules that allow for capturing ones own pieces could certainly apply to one's partner's. Play would require teams alternate moves.