Im really not sure what to tell you here, I just went thru the whole process of a purchase, site is working as it should be and orders having been coming thru steadily since it came back up. If it wants you to login, then you should login. Sometimes the site will look like your logged in but you are not.
Please explain. Are you getting to the "option" of using Paypal on the JR site, or are you actually getting all the way to being redirected to the Paypal site, where Paypal is asking you to log in to Paypal to complete the sale? (must log in to Paypal AND JR sites both to complete sale)
Up in the top right corner of the JR site, where your name is, does it say "log in", or "log out"?
--Do you have Cookies Enabled? (must accept Cookies to Log in to shopping cart)
After you do the Paypal part, and are redirected back to JR, you must accept the terms (check box), then click "Update Order", then click "Submit Order".