I am using version 8 platform update 15. Since the POS development is locked out and extensions only is allowed. There are some limitations and a number of objects are not accessible.
I was trying to navigate to the customer search and allow the user to select a customer and return to the calling form. This was very challenging.
One possible solution I found is to use Global variables. I used the window object.
To do this, declare the window object as per screenshot. And then just set your object :
eg. window.MyVarName = WhatEverObject;
To get the value just invert it.
You can see how I have the customer object in debug.
Credit to one of my colleagues who suggested this solution.