Can't install any plugins. I get caught in and endless loop

Can't install any plugins. I get caught in and endless loop from the plugin page on your website (https://premium.wpmudev.org/project/snapshot/) back to the WPMU DEV Admin plugin preview page. When I click DOWNLOAD PLUGIN, i get directed back to https://premium.wpmudev.org/project/snapshot/ and the loop continues. I';m trying to install on http://www.sidelinesportsdoc.com/usclubsoccer/