When I run "Preview without saving collections"nothing happens. I have tried running it from the drop down and the "Customize plugin" screen. I have also made changes to "Configure which Kindle collections to update" and I experience the same result.
I get this pop up every time:
calibre, version 0.7.49
Kindle Collections plugin: Welcome to the Kindle Collections plugin.<P>Run "Customize plugin" to configure which collections to create.<P>Run "Preview without saving collections" to see a test report.<P>Run "Create collections on the Kindle" to save collections.<P>
Using a Mac and a Kindle 2.