Yeah, SWS site seems down currently for some reason.
You could alternatively download the build cfillion made (which compared to the current official version additionally contains a rather important envelope manipulation fix):
https://forum.cockos.com/showthread....84#post2095284
(Doesn't come with a 'fancy' installer though as the official version, assuming you're on Windows, just drop the .dll in [Reaper resource path]/plugins, (re)start Reaper and it should get picked up.)