The latest MRSS example channel is v1.2.1 https://roku.box.com/s/d834c57fcc831b498423
The example channels are meant to be a starting point for developers to build on. We never intended them to be something people could copy/paste data into and have a finished channel. I agree we could do a better job with documentation, but as a developer you're free to develop whatever additional functionality you want on top of an example channel.
Maybe I misunderstood your last sentence, but I'm not sure why you think you need redo your channel to add a manifest splash screen. That doesn't even require a code change.