I finally gave in sitting on the Gap5 tree for so long and built some binaries for public release; 32-bit and 64-bit binaries for linux only. See the download section.
Please note this is very much a test release showing how development is coming along. It lacks all sorts of things needed for use as a production system including docuementation, robustness (there are lots of bugs I know of but haven't yet fixed), missing features and even stability of the file format. Don't expect gap5 databases produced by this code to necessarily work with subsequent gap5 releases (although I'm working on ways to stop this from becoming an issue long-term).
Sorry I cannot support queries on how to get this working. The binaries may work for you (my development host is rather old, running Debian Sarge), but if not I do not have free time currently to build new ones for your specific platform. This will be dealt with once I start getting to what I'd consider robust production quality releases.
As always though, source is in CVS for the (very) intrepid amongst you. If there's anything missing there then it's an oversight and please let me know.