That is up to you. The minimum is an email address. You can optionally choose to submit the user's first and last name and other data that is relevant to you.
Yes, you don't even need to contact support for that although we're glad to assist with any questions you may have.
Yes, you can do that from the Organizations > Invites screen.
Yes, you can even use the same account across multiple organizations comparable to how e.g. GitHub works.
We've put considerable effort into making Sprouted secure. Check out our Information Security page for details.
Yes, it can be found here.
Not at this time.
Yes, just let us know which data format you prefer and we'll provide a downloadable file with all your data.