Most people are likely going to remember for the first 500 or so years, but odds are the information is going to become so muddled that people are going to start forgetting things. Remember 40k is big on the idea of lost knowledge and the idea of it being a cyclical event.
Yeah, but the printing press is a technology only restricted from the more primitive feudal worlds. I'd imagine that every Imperial citizen, even the ones who aren't real believers have at least one bible-equivalent in their home. With a society like the Imperium, they'd make things like the pocket bibles being handed out on the streets look really tame.
2. Where are our stormtroopers? When we built the Schola it was said we'd get stormtroopers but the closest we've gotten are grenadiers in the form of the Hellguard.
Stormies are very similar to Grenadiers really. Especially with how GW in their infinite understanding of scale limited them to a couple hundred thousand.