Below is an extract of a post of another user who was having problems connecting his B2 to his Mac.
Hi,
I've been following this thread as I just upgraded my MacBook Pro to OS Catalina, 64 bit, losing access to all my 32 bit software and, coincidentally, to the Brennan B2.
What Peter says in his message of 31 March definitely worked for me:
Finder
Go
Connect to Server
Enter SMB://IP of B2
Add this as a favourite server once it works
I had to try twice - it doesn't always connect the first time. Use the usual Brennan B2 name/password when challenged.
Kind Regards,
Tom.