You are in control in what order your auctions appear in the catalog. It means, that you can lock auctions to appear in a specific order.
Navigate to omniAuctions \ Manage Auctions \ Categories \ Auctions.
- Select Category you want to manage.
- Turn on Order option to show auction order.
- Order Auctions from 1 to N. Every time you leave order field for an auction, that order number will be saved.