You install it on a computer that has neither Roon Server nor a full Roon client. You might also need to fiddle with the firewall to give it full access to the internal network. After that the computer with Bridge would be seen as yet another Roon Ready endpoint.
I’ve already got one in for support because I can’t see any outputs on any machine running roon apart from the one running the server. I suspect that the issues are linked so will wait for the problems with standard roon to get fixed and then see if this one is still here.