You shouldn't check anything if the channel itself doesn't have any requirements. Those checkboxes make the channel so that it is only available on boxes that meet those requirements. So, the one that you published with the usb support option checked will only be available on the top-end Rokus, as those are the only ones with a USB port. Likewise, if you checked the "Roku 3" option, then the channel will only be available on Roku 3 devices.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
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