Hi LoLo,
If you no longer need the error messages on your scheduled listings page for reference, you can go ahead and delete those. However, if you need assistance getting those listings that failed to post posted successfully, please file a support request using the appropriate link on our help page:
http://www.auctiva.com/free_auction_software_help/help.aspx
Any listings you post through Auctiva, whether they are store items or auctions, will be displayed in your eBay store, as well as your Auctiva store. A selection of 14 of your current listings will be also displayed in your Auctiva store window at any given time.
-Mike