In case you’re wondering – we had updated most of our plug-ins a while back, shortly after InDesign CS5.5 was released, and made CS5.5-specific versions available.
As long as you make sure to install the CS5.5 versions of our plug-ins (instead of the CS5 version), things work fine in InDesign CS5.5.
Check the individual product pages for the necessary download links – we’re currently restructuring our web pages, and in most cases, the download links are now represented as clickable buttons at the top of the page. On some pages the download links might still be buried somewhere mid-page. Sorry for the mess – we’re getting there!