I think McCoy, Scotty, Uhura, Sulu and Chekov (?) were all on board.
Yes. Walter Koenig was told that he would be wearing red, and heading Security. The red Starfleet Security shirts made for "Phase II" were repurposed for Orkans in "Mork & Mindy".
Of course, when a fully-recast Trek movie, with Really Big Names as Kirk and Spock (ie. the calibre of Paul Newman and Robert Redford), was being considered, Gene Roddenberry ran into Walter on the Paramount lot one day, and offered him the chance to play... Chekov's father. (This anecdote is in "Chekov's Enterprise", IIRC.)
I just pulled my copy of Star Trek Magazine from Dec. 2001, the TMP issue. It features an interview with Collins about the movie.
No Will Decker had been cast before "Phase II" turned into TMP.
"The Making of Star Trek: The Motion Picture" listed the short list of candidates for Decker. One of them was a young Andrew Robinson (the future Garak) and another was Tim Thomerson (the future Jay Allen, Barry's older brother, in the pilot of 1990's "The Flash").
Last edited: