Editing the note values of metronome marks

This is an unusual situation. I'm working on music that was originally printed with pendulum tempo markings. I have no problem entering these, but in certain instances, when I enter the standard metronome mark that has a different note value than the time signature indicates (ex. if I want a quarter instead of a half note in cut time, necessary to match the original pendulum marking), I am unable to edit the note value. Also, if I place the metronome mark first, as long as the note value matches the time signature, it appears correctly. But if I want the standard bpm marking to be editorial (in parenthesis after the pendulum marking), the note value turns into a boxed question mark.

I have tried copy/pasting quarter notes from other metronome markings, to no avail. They all appear as boxed question marks. Is there a way around this? Thank you.