McQuarrie labels the corridor as Vulcan, but the curve makes me think Enterprise interior.
But it might also represent the interior of the dome shown in the sketch just to the right.
It could, but bear in minds that these images are not necessarily grouped together due to being related. The two images to the left are in the Art of book, the two at right are not. Since they don't appear nor are 're not captioned in the book, I can't say it's likely or impossible.
As to James Shigeta, he's a fine actor, but this thread's about Planet of the Titans
and not Phase II/TMP
casting minutia: I'd like to keep the focus on Titans