Hello,
If you want the vendors to receive ALL of the funds from their sales, and pay the admin no commission percentage, you would enter 100 for commissions.
If you’d like the admin to receive all funds from sales, you would enter 0 for commissions.
If you are referring to the email bug where it does not show the correct commissions total- that has been reported and will be fixed in one of the next releases of WC Vendors.
The total for product sales is correct, though.