I know it’s been quite a while since the 0.5.3 release of the hgd server, but I finally got around to completing the latest version of hgdc-x, the cross-platform GUI hgd client. It is compatible with any of the 0.5.x versions of the server.
Changes include numerous bugfixes, a redesigned GUI and a better user experience. There are pre-compiled binary versions for Linux, Windows and Mac (Universal binary for Tiger 10.4 and later).
Get it from http://hgdcx.canthack.org