I finally got the client to connect, but the traffic is not routed through the VPN server.
I found this:
https://gist.github.com/ViRb3/98c7cbb0b40d51c9da0965725eeef279
Which says to check "Allow other network users to connect through this computer's Internet connection" for the TAP adapter. But as soon as I check that and click OK, the internet connection on the server itself is lost.
Anyone have any idea why?