A keyboard shortcut can be added as follows:
In order for the shortcut to persist after you close and re-open InDesign, make sure that you have version 1.0.3 or later of in5 installed. You can download the latest version or check your version by clicking Check now... in the Info section of in5.
Shown in this video: https://www.youtube.com/watch?v=i2nf0LUfXUA
Good enough, thanks Justin