Brian,

Please detail the exact steps which cause this problem for you. Your post isn't clear.

When copying and pasting, the only transposition which takes place is if you're copying and pasting to a staff with a transposition. (like copy & pasting from a flute staff to a clarinet staff)

If you change a key signature to a selection of music which has already been entered, then you are given a choice how to handle the transposition.

I exported a midi file from my sequencer, as I wanted to update the harp in Finale from my changes in Studio One.  I opened the midi file in a new finale file, then did a copy and paste into my existing finale file for my opera.  Everytime I had a key change, the paste removed it and transposed the notes, when no transposition was needed or desired.  I submitted a ticket already on this.  Do you have access?  I posted my files as examples so that it can be recreated.  I had tons of cleanup to do, as I didn't realize it immediately.

I'm a user, just like you. You'll have to wait and see what MM says. Their support team apparently is backed up at the moment. So it might be awhile before you hear from them.

By using what you described, I was able to partially recreate your issue. The problem is, in Finale, when you copy and paste between different files problems occur.  The files should be in the same key and meter.

My only suggestion, in the future when you need to do pasting between documents, it's helpful to make a backup of the file before any copy & paste is done. If something unforeseen occurs, you then can always go back and try something different.

Thank you for looking into this, and for clarifying that you are a user like me.  I believe that it may help to use a filter when copying, so as to only copy notes, but I need to test this hypothesis.  Either way, a warning is in order if the potential for unexpected results exists.  I was told to post here after hearing back from MM on my ticket about this.