Oh I see. I was under the impression you were on WAMP on desktop due the subject of the thread.
Well it's a windows server, with apache, mysql, and php, which is wamp.
Anyway, to 'settle' this to some degree, I downloaded the single WAMP install program, installed it on my clean laptop. Made the changes to get mod_rewrite working, and anyway, after a couple of restarts, I got silverstripe installed there.
The install is pretty bad, it kept complaining about mod-rewrite not working, but it was definitely working fine.
Anyway, now that I did manage to get it installed once, I'll have a baseline to see how my server's configured differently from the laptop. If I figure out the real problem, I'll post back.