What specifically isn't working? It's been long known that the Stop button no longer works at all, but hitting the spacebar still does. 

The few times I've had to return to Finale to make some minor edits to old scores, there have been a ton of issues in terms of expressions and smart shapes (esp the latter), none of which were fixable with uninstalling and reinstalling Finale 27.4 from the downloaded installer. That does not seem to have happened to most folks, but the Stop button issue is universal. 

Nothing you can do to fix it. Finale was more or less abandoned nearly two years ago (and longer, probably, given how bug fixes never really came for issues reported in 2023). 

Jan Angermüller (Elbsound Studios, Perfect Layout, etc.) is currently testing an app that fixes all the misfunctioning buttons, "Tahoe fix for Finale".

If Jan’s patch addresses this issue (more than just the Stop Playback button quirk) that would be great. But long term, there will be more and more problems as Finale is not open-source and even if it were, the code is likely a mess of patches upon patches that would require a complete rewriting to really keep it going. Thanks.

Seen on Facebook, a post by Jan :

"Jan Angermüller