I've downloaded and installed it but it does not accept any plugin folders. I can select them but they all appear empty, there are no plugins read from these folders.

Any hints?

I drafted a comprehensive reply to this and then this ridiculous forum software through it all away, so my apologies for the brief (second) response: Consider whether UAC has moved the plugin files eslewhere. Plugin folders are best kept away from UAC's control.
Check that the plugins are not within a zip file while appearing to be within a folder hierarchy

Otherwise, please provide screenshots of your setup so that I can diagnose the problem further. This issue has not been reported previously, so I don't have a ready solution. 

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