Responsive Layouts with InDesign and in5 are created using InDesign's Alternate Layout feature. One of the requirements for making this type of Responsive Layout is that the page counts must be the same for all Alternate Layouts. Because a desktop layout can include more content than a mobile layout, there may be more content than what can fit on the smaller page.
Here are some approaches that can help you accommodate the excess content.
Create a Scrolling Frame
Scrolling Frames let you group larger content and paste it into a smaller frame. When you go to in5 > Interactive Widgets > Scrolling Frames, you can set the direction you want the content to scroll.
For more information about Scrolling Frames, see Universal Scrolling Frames for InDesign.
Add a Multi-state Object and Buttons
Multi-state Objects (MSOs) let you make groups of content that can be viewed as separate object states. Use buttons to navigate through the object states or create a Slideshow from the MSO by going to in5 > Interactive Widgets > Slideshow.
See the following for more information about Multi-state Objects, Buttons, and the Slideshow interactive widget:
Export a separate document and embed it
You can create a separate document with the excess content, export it, and then embed that output on a page of your Responsive Layout's mobile layout using the Web Content interactive widget.
The document that gets embedded can be exported using any page format. For example, the content could scroll when the Borderless Page Scroll (Vertical) page format is selected, or it could advance like slides using any of the Slider page formats.
To embed the content onto a page in the mobile layout, draw a rectangle, go to in5 > Interactive Widgets > Web Content, and navigate to the index.html file of the exported content.
For more information about the Web Content interactive widget, see Web content.
To learn more about how to create Responsive Layouts with InDesign and in5, see this article.