Ray, I am still having the same issue. I deleted the pages, both locally and on godaddy. I uninstalled and reinstalled the ecart extension, and confirmed that DW is up to date. Also, I thought it might be due to working remotely on my laptop. Sadly, I have the same error when working on my desktop.
I do not have any errors when running the wizard. It does have a pop up about 1/2 way through running the wizard, stating the confirm_cart.php has changed and asks if I want to save it before putting it to the server. If I click yes, then it stops working because the server is already in use. If I click No, or let it time out, the wizard completes without apparent issue. However, I am continuing to have the same error.