These days if a site does that I go elsewhere - the trouble is, I really want to shout at them to tell them why I am going somewhere else but there is rarely a useful contact to do so.

I got this working today with it running on a Pi as a server and on a Mac mini (M2 pro chip) as a client. Works very nicely. It fails on my Ubuntu machine though but never mind, early days, and it might just be my config.