1 & 2: As for kingdoms and duchies regulating technology, I'd argue yes, but only to a certain extent. Kings will have the most power to decide whether or not their kingdom focuses on technology by allocating certain tax dollars for research. How detailed these mechanics will be is yet to be announced. I'd be surprised if the king couldn't specify he wanted funding to go towards military research, but it's speculation at this point.
3: Guilds and schools do have harder rules because there will be in-game mechanics to support them. Guilds are primarily commercially motivated and schools work towards education and research. Associations, a third type of organization, are more flexible as a sort of social/catch-all category. Think of it like how standard MMOs use guilds or clans. You might find this page on the wiki a helpful summary of the different types of organizations in CoE.
4: If you haven't already, you should definitely check out the DJ on Technology and Research. Here's a relevant excerpt about sharing technology:
"If you perform research on the equipment of an organization, such as a Guild or School, you're implicitly agreeing to share all discoveries you make with the institution. The effect is quite different depending on the institution. If you make a discovery as part of school, they will turn around and make the information freely available to everyone. On the other hand, a Guild will often go and Patent the technology, granting them sole and exclusive rights to utilize the new knowledge."
It also explains how patents work:
"Patents give the owner exclusive rights to use a technology for a period of three real-world weeks. After the first three-week period of time the owner can request an extension for another three weeks, however this is often very expensive. After the full six-week period of time, or if the owner chooses not to file for an extension, the patent falls off and it becomes acceptable for anyone to create the technology."
Hope this clarifies things a little!