For anyone that read this post initially, I did more trial and error and totally re-wrote this post to explain what is happening.
Today I installed a GE Z-Wave paddle lightswitch, and an accompanying GE add-on switch. They are working great for manual toggling of the lights. I am having some issues with Smartthings though. I have paired the main switch with Smartthings. If I open the Smartthings app on my phone, I can toggle the lights on and off as long as I am standing right in front of the main switch or within about a 2-foot radius of it. As soon as I take more than 2 steps away from the main switch, I seem to be unable to control the switch using the phone app. I dont understand how the proximity to the phone should have anything to do with the control of the device. My phone should not be related at all to this lightswitch. I should be able to turn this light on and off using the app from anywhere in the world. What am I doing wrong?