Re 1: I think you mean that I have a green dot by the USPS module, which I do.

Re 2: Looking into this -- perhaps the most likely cause.

Re 3: I assume it's the Postal Code in the Configuration > Shipping/Packaging menu you're talking about and I'm using a Zip 5 format (no +4).

Re 4: I've triple checked because the steps are so simple. I don't think this is the problem. I've also verified that online version and my local files are identical with the Zip file that Dr Byte posted.

I'll check back when I know about #2.

Thanks!
Tim