What's interesting is the part how multiples worlds are apparently terrified of the No-God. Was this something the Inchies tried on other worlds but failed? Because it seems from the Bakker writing we have so far that Shae helped conceive the No-God?
It could be that Earwa is special in that the No-God must be manufactured there, but all of sentience feels its presence...
How would a world full of sentient beings interpret a feeling of presence looming over them in the sky? All the Earwans could feel where over the horizon the No-God was, which amounts to North/South/East/West, so what would others sense? To a group of people, even spread out all over a planet, it would seem like there was something always in the same place.
Seems to me like the presence of a God somewhere out in the sky. All those alive at the time would have this new feeling of being watch from the sky, but all those born after its existence would not notice it. Then after there would be a few generations of those that would notice its absence rather than its appearance, and after that there would only be stories.