I must admit - I'm only still here to keep people updated on a completely different issue but, given that you have experienced this issue for over a week, I will say that it is not the result of the issue I described. One thing that could cause that is if the token associating your Auctiva account with your eBay account is invalid.
If you do just need to generate a new token, you just need to click the "Ebay Settings" link under the "My Account" tab within your account and then click the "Get New Token" link on the ensuing page. If your token was invalid and you generate one, your closed listing should resume importing in 6-8 hours or so.
If you already have a valid token and your listings still don't import, I recommend filing a support request using the web form on the following page of our site: http://www.auctiva.com/help/requesthelp.aspx