Over-eager "remove" in Instruments dialog.
(3.4) I was trying to delete many parts from a score with many parts, just saving a few. I carefully deleted the few above the parts I wanted to keep, and then clicked on the first one after them that i didn't want to keep, and clicked "Remove" many times. Surprise! Once it got to the bottom, it started removing parts upward, i.e., the ones I wanted to keep. This is not right. If you Remove the last part, it should not leave any part selected. I had to count very carefully to achieve the simple thing that I wanted, and do it two or three times until I understood it was trouble "not with my set, but the station" (as they used to say in the days of broadcast TV).