Hello Cynthia,
as you probably know this is a public mailing
list/discussion group of an open source project, with most resources available on GitHub. There is, to my knowledge, no "main developer", so you'll
probably not be able to get any "official" answers.
> 1. Is there an organization which sponsors/publishes the project, or a
> primary developer who audits the code for potential vulnerabilities,
> errors, or malicious code? Y/N
I am not aware of any activities or a sponsoring like you described. These would usually be listed in README.md[1]/THANKS[2], would show up in security advisories [3] or be visible in commit messages [4].
> 2. Please list the country or list of countries where most
> contributions originate from.
PartKeeper
was originally written by "Drachenkaetzchen" with "christianlupus" also
showing a bunch of additions [5]. Both share >50% of committed lines and
are – according to their profiles – located in Germany.
(Just to make it clear: I am just a user, not involved in development of PartKeepr and just pointing you to public resources.)