Multiple Instrument Changes CRASHING

Hello all, my issue is I am writing a percussion heavy piece which requires three percussionists to change instruments frequently, and I was using the new "Change Instrument" feature in text, but for some reason I am 57 measures in and cannot do any more instrument changes in any of my "Percussion" parts. The only part it will let me do is the Timpani, but the timpani player is not the staff I want to have to write a marimba part in.

Every other part is fine and I can use the system there, but for some reason Musescore continues to crash whenever I try adding another instrument change to my percussion lines. Please get back to me as soon as possible as I am using percussion to continually push the piece forward. Thank you!