Pre-Register Bidders - applies only to live events: Do Not have people "pre-register" online (on your public auction webpage) unless they are actually bidding on items online. Bidders will only show up in your Bidder Management if they have actually placed a bid on your auction.
Keep in mind if they "pre-register" they will not be part of your auction or show up in your bidder management until they are an active bidder on your auction.
For example: Someone pre-registers online, but does NOT place a bid on your website. He then comes to your event and places a bid on the silent auction bid sheet and uses his bid-number. When you try to record the bid in the system, the bidder will NOT show up, solely, because he is NOT tied to your auction. The person is a BiddingOwl customer, but not associated with YOUR auction. This is to protect their privacy.