Read everything. I have good news but it takes awhile to get there. You can do what you want but not the way you think you want.

Specific case: I have a number of libraries installed. Some require dongle authorization. Some require external HD access to sounds.

This is true of every audio app or DAW that uses plug-ins. There is no workaround that lets you exclude Finale.

Is there a way to disable audio units from loading?

Yes — but no application will be able to use them. Do you want that?

AUs are stored in Library/Audio/Plug-Ins/Components. You can either remove them or create a folder inside Components called Disabled and drag all of the AUs you don't want loaded into that folder. Of course, before you use a DAW or any other app that requires those AUs, you will need to drag them out and put them in the proper location again.

When I am away from my desk and just want to run Finale with NotePerformer 4, is there a way to disable those other units from trying to load?

Bottom line: when I use Finale on the go, I just want to use NotePerformer sounds.

 

Yes!

You need to create an APFS Volume on your System drive (do not Partition your drive), install Sonoma and Boot into it. Install Finale with NotePerformer plus any other apps you need to access. It will have its own Library/Audio/Plug-ins/Components folder but you will only install NotePerformer. Apple has plenty of documentation on this and can walk you through the process. 

Since you mention that you have NotePerformer. Installing or updating NP will force Finale to re-examine all of your plug-ins. If you have hundreds as I do, Finale may crash a time or two the first time you start up. Just reopen and eventually they will all verify. Do not uninstall/reinstall NP or the process begins all over again. Once verified, you won't see it again till the next time you update NotePerformer.

It was Arne Wallander who helped me diagnose this a few years ago. Why Finale must re-verify everything once NP is installed or altered is a mystery to us all—but it does. Normally, Finale only verifies AUs that have changed.

I really appreciate you taking the time to give such a detailed answer, Mike. "Community Expert" is an excellent description!

I will consider your suggestions carefully.

In the meantime, after several faulty starts, Finale is behaving (somewhat) normally again. Each time I think I've been patient enough with restarts, it always seems like "just one more" is the answer. : )

And, it doesn't seem to be looking for all those dongle-authorized AUs (for now), so I can work away from those as desired.

Take care, and thanks again...

B