To edit images you need to open them in Photoshop.

Photoshop needs to be running and you must be logged in to GN4. Select the images you want to edit and choose the menu Plug-Ins>GN4>Edit or context menu GN4>Edit.

This will open the images in Photoshop.

Please note the software will only share data between InDesign and Photoshop in the same version, i.e. works between CS5 versions or CS5.5 versions but does not work if InDesign is CS5.5 and Photoshop is CS5.