Try exporting (in5 > Export HTML5 with in5...) with the Page Format set to one of the Slider formats. Here's more info:
You can use Presentation Mode when the Output is set to Multi-page web to enable keyboard navigation. Here's how:
Myra's solution above is the best way to get the navigation to work with keyboard arrows. I saw your other question come through as well and requested that you send files so we can help you troubleshoot.
For anyone else wondering about this and for the in5 team, I actually found a way to add keyboard navigation without turning on presentation mode (the keyboard navigation that presentation mode uses has next assigned to up, right, and spacebar, and that spacebar broke our notetaking module since adding a space between words would advance the page).
All i did was find the function that is added to the in5.config.js when presentation mode is turned on that reads:
So i snagged that code and modified it to remove the spacebar keycode (32) and removed the (if presmode.keynav) wrapper and appended it on export as a js file. works great! Final js below: