I have quite a few channels on Roku already, but lately I haven't been able to get any new channels through the "PartnerSuccess" team. Each time I get rejected because of my screenshots and because of the fact that the InstantTVChannel screen comes up before getting to the channel.
The Roku web interface (on your development Roku on your local network) has a screenshot button under Utilities. That's what they want you to use to obtain your screenshots. You have to be running your channel sideloaded. Click the screenshot button then save the resulting image to upload to Roku. hope it helps.
As of last February, Roku requires your own splash screen instead of the place-holder Instant TV Channel screen. All that you need to do is to provide your own 1920x1080 and 1280x720 splash screens and it will replace the Instant TV Channel splash after the next package file is generated & uploaded/published to your Roku Developer Account.
Screenshots have become problematic over the past several months. Currently, with few exceptions, they do not accept screenshots that are framegrabs of videos in your channel, that show the unique content of your channel. Instead Roku wants screenshots to show the menu screens. It seems counter-intuitive to me that the menu screens would be of more interest to a potential viewer than the actual video content... at least if this is a video channel and not a game or utility channel... but that's what Roku wants. You do not need to provide screenshots, they are optional (for now). My feeling is that without screenshots more potential viewers will install the channel, just to see what it is, which I suspect will also increase the channel's ranking in the Channel Store.
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