As Jaret said, analysis and conclusions can be found on the last few pages of the report. To briefly summarize, however, I believe that the Drifter Hive systems represent areas of heavy scientific research, where some race (either the Drifters or the Sleepers; it’s a little unclear) is attempting to reverse engineer the Talocan Static Gate technology. Most, though certainly not all, of the sites appear to revolve around different spatial fissures, with machinery surrounding the various types of fissures in attempts to stabilize them.
A few other areas seem to represent either battlegrounds or attempts to colonize various areas. Exactly who was attacking what, unfortunately, seems to be lost to time, but clearly something tried to interrupt the research. It’s unfortunate that many of the sites appear to be fairly old, and that more detail was not available.
I hope this helps, and of course, if you’re interested, please feel free to peruse the full report.