On the conditions for royalty accrual

Nice to meet you.
I would like to know about royalties for releasing non-game content using the unreal engine.

I understand that royalties are due if sales are over $1,000,000 and quarterly sales are over $10,000.
Is it correct that the royalty calculation is 5% of the quarterly sales?
Am I correct in understanding that the royalty is not 5% of the cumulative sales up to that point for each quarter?

Also, is it my understanding that the above royalties do not accrue when you sign up for the Enterprise Program, and that you only need to pay the monthly subscription fee?

Kind regards,