I have been testing progressive changes to the WP Super Cache trunk version with both WP 3.3.2 and WP 3.4 beta running on Windows Servers over recent months. Those changes have fixed a variety of problems that had made WP Super Cache 1.0 unusable without custom patches. I haven’t tested legacy mode, but mod_rewrite and PHP modes now both work as expected using a Windows Server with Apache 2.2.22 and either WP 3.3.2 or WP 3.4 beta.
The one remaining frustration is that option selections are not persistent when WP Super Cache is deactivated and then re-reactivated. I understand why they are not from studying your code, but I think that is a rather serious flaw where someone can take down a site merely be deactivating and reactivating a plugin.
Wouldn’t it be better to save user option selections in the database as metadata to avoid that problem? If there is some reason that is not apparent to me that makes that impractical, what about making it possible for users to save a persistent configuration file their theme directory? That would be a less desirable solution, because that file would have to be modified from time-to-time to remain compatible with future WP Super Cache versions changes, but that would be less of a problem that losing option selections each time WP Super Cache is temporarily deactivated.
Thanks for all the work you have done on this. Your new version has been greatly improved compared to the previous release.