I had to download the HLDS. Currently I'm running one server and it works, but when I replace the original HLDS with ReHLDS it doesn't start any more. I tried using metamod-r, and disabling everything in metamod's plugins.ini, but that didn't work either.
I remember now that I'd fooled around with ReHLDS a year or two ago and I'd been able to at least run it. The only difference is that I was running HLDS 6153 at the time.
BTW, the server's FPS drop to under 100 when there are players on the server, but is ~500 when there are no players, will ReHLDS be able to do better ?