OK,
I had some spart time to prove my premise of CV conflict(s).
I took the original MPC, edited the number to 294, and sized that text to 4.6" high. It passed muster! I then went back and uses the original number, but re-sized the height to 4" and made sure the the text was equally spaced from any higher edge. This also passed muster with no error. I made no other change to the original MPC!

This proves the software was, indeed, concerned with the mechanics of the moving parts striking a higher surface and causing an abort.
AskBud
29448 Conform-4 inch.mpc