Got your email too, but I'll answer here as it may benefit others.
At first glance, it appears that your scenario is as follows:
- using the advanced method to cache images locally
- using the lock to account feature
- entered in domains (not IPs)
So whenever you are using advanced method, the referrer is the server IP. Therefore, you need to enter the IP address of your server when using the "lock to account" feature. Since it might be easier for you to get going quickly, I simply turned off "lock to account" for now. It is rare that credentials are misused anyway and not likely by the time you sell your site.
However, because you seem to be caching the error images, you need to refresh your cache. Some of our sample code would help to eliminate caching the error image but it probably doesn't matter as much, since you are selling the site.
Aside from that, I see no reason why you would get the banned message (unless your IP is banned for multiple accounts or something but to check that I'd need to know your server IP).
Hope that helps!