How to control beta stream app on Samsung TV

When I first installed the app and ran it, the main screen with all the options appeared. After selecting live TV and a channel I can no longer get to the main screen or the large channel guide. Every button on my remote that does anything simply brings up the same few icons on the bottom, one of which I gets me to the mini guide and another precious channels. How do I return to the main screen?

When I choose the channel list button on my remote it selects the channel list from the air channels, not the app.