Hi,
It is not iframe inside an iframe issue. There is only 1 irframe to open the registration form, but because of the limited width issue, it generates an another scroll bars inside the iframe... anyway.
That issues has been fixed already in the new version.
But you are not eligible to receive updates for free and also i am seeing you have made lots of customization on it. So i should better access your website and apply the patch individually to fix that layout issue, and you will be good to go without losing your customizations.
Can you provide me your Joomla Admin account or FTP credentials to This email address is being protected from spambots. You need JavaScript enabled to view it. and let me patch that layout issue in the shopping cart page?
(while emailing to This email address is being protected from spambots. You need JavaScript enabled to view it., don't forget to include this forum post's URL at the top of your message to avoid any possible confusion in our end)
Regards.
Forum Support.