Permalink Error 404 ShopperPress 7.1.4

I am getting an error on my shopperpress site when my product go over on to 2 pages:

Admin Help: Why am i seeing this page?
This error 404 page means that for some reason the page could not be found or loaded correctly.

It maybe that your WordPress permalink cache needs refreshing, click this link to view your admin permalink structure then come back and refresh this page.

If the error continues try checking your website link is correct in your browser window or re-creating the page from scratch.

Note: You are seeing this page because you are logged into an admin account, normal website visitors will not see this message.

I have Shopperpress version 7.1.4 installed. And I’m getting confused as to what is the latest version. I read on another community post that I need to upgrade to latest responsive theme to work with the new WordPress, however, my theme says ‘congratulations you’re on the latest theme’, so I don’t understand?

a) How do I fix the permalink error
b) What is the latest version and how do I find out?

Thanks
Zoe Sterling