After you have moved your mouse pointer on your dashboard over a publication cover and clicked on LINK EDITOR, you enter the editor, which opens with a page overview of the publication.
On the page overview, click on the thumb of the spread on which you want to add interactions. Next, the publication will open at that spread. On top of the spread you can select the interactions you want to add (URL and page links) and enter the desired settings. Click outside the frame/interaction to save it. Move your mouse pointer on the spread over the interaction and click on it to edit it again.
Click on PREVIEW to preview the current status of the publication.
Click on PAGE OVERVIEW to return to the page overview.
On the page overview, click on GENERAL SETTINGS to edit the general publication settings (e.g. language of reader and layout settings).