Tuning plugin musescore 4.5.1

How do I use the tuning plugin???? I'm trying to make my piece sound a quarter-tone sharp in playback, and so I used one of the empty temperaments and modified it to +6.5, but when I try to press "Apply", it tells me I have unsaved changes, and when I press "Save", it doesn't do anything. Idk if this is a bug or something, it's just frustrating. I uploaded a screenshot of what I'm seeing.

Thanks!