How to start editing a photo with the configurable external editor?

Hi,
I can configure an external photo editor in FM5. I thought I could use this setting to start off the configured editor on an image within my slide show to quick edit and adjust it. However I do not know how to trigger and startup the external editor from FM5? What do I need to do and from where (Storyboard/Timeline)?

Many thanks for any help!

Cheers
Joerg

To trigger the external editor that you have chosen from within the Preferences > Authoring tab, you can double-click on the image (or movie) that appears in the browser window (on the right side of the screen). You can’t do it from within the Storyboard or the Timeline.