Doh!
I just realized that I had an older version of it on the system I was using at that time - the current compilation is fine from that and all the other rotated airfields I've tried. (and No, I just placed it as a single object in the TE, and rotated the entire object, making sure that it doesn't overlap a cell border.)
Sometimes a few minutes more time up front checking things out before asking is well worth it.
And maybe someday, I'll get it finished, and can move on to the next - probably just after some major change to the game and I'll need to redo it anyway.
I kind of got sidetracked, and have been building tools to do what I want to do, rather than repetitively doing things by hand.