I understand that it is purely a matter of choice, but what are your reasons for having SSL on an product detail page? I can understand it for customer registration details, login etc.
I imagine the error is occurring on your last page because you have switched back to your own domain, for which you don't have a valid SSL certificate. It looks like you are using Fasthosts (eek!) shared SSL space rather than having an SSL certificate installed on your own site.
If you don't have an SSL certificate on your own domain you will generally get errors thrown if you try to access it with , when it needs to be http://