I am running into a similar problem with using the SIM module for Authorize.net transactions.
What happens is I arrive at the hosted Payment Form, I fill it out and submit it. The next page - whether it is 'accept' or 'decline' - goes back to a page on my site, though the URL in the browser is still that of the hosted Payment Form (https://secure.authorize.net/gateway/transact.dll).
All of the CSS styling is stripped out of this page. Come to think of it, I don't see any images on the page either.
When I click on any old link, then the URL returns to actually being something that belongs to my store with all the styling.
So I don't have an SSL (yet) but it sounds like I am getting the same problem as I would get with an SSL which does not have the correct hostname as the original poster described.
I'm wondering if anybody can help me parse what this might mean with regards to getting this to work correctly... what this might indicate. I don't think there's any settings in my Authorize.net account which would affect this. I've gone through Relay Response and all the rest. (did I have to tell Authorize.net the EXACT hostname??? I don't think so...)
FWIW, I went back to a site I did last year. Same webhost, same version of ZC, same SIM implementation. It worked fine. When I got a card decline, it returned me to step 2 of 3 page (checkout_payment, I think) with all of the CSS styling applied. It won't do this with my store.
Help, please...
(and please don't tell me I should be using AIM, I've had quite enough of being nagged about that thankyouverymuch)
