I think you're lucky your install is working... I can't get the combination of wp 2.9.2+standalone 188.8.131.52 + slidepress 1.3.7 to work... the swf is there, just no images and no navigation -- no matter what.
That said, one other bug in slidepress, imho, is that CHECKING the THICKBOX option in slidepress actually disables it, UNCHECKING enables it -- completely counter-intuitive, but hey, that's just my two.
But if your gallery is opening in a popup, that might be the issue. If you go to the SlidePress Bug Report setting page, you can read your system settings to see if thickbox is enabled or not and compare that to whether the option is check or unchecked in the setup settings.
HTH -- wish I could get a response from ssp/slidepress folks, too. I've sent 3 bug reports, 2 direct emails to both todd and scott and posted ad nauseum in the standalone and slidepress forums.