The server is running on a NAS on my LAN. It works perfectly for two different (paid for) users from their official MOJANG clients on Windows machines.

I am trying to set up a client on my Mac and I cannot find a way to connect to that private server.

My server package is old (1.5.2) and I know I have to match the client to the server version for Mojang, is there a similar issue with the World of Minecraft client?

When I try the connection via minecraft.net the error I get is "connection reset" and "lost connection" on the server.

When I try the connection via the direct url I get a protocol error on the server.

The Mojang licensing model seems to suggest I cannot use one account for two different installations, so maybe there is also a licensing model here and what I am really being guided towards is buying yet another subscription with Mojang on my Mac.

It'd be good to know if I am supposed to be able to use the World of Minecraft client with a private server.