Our design store offers a big yellow "PayPal" button on the checkout page. That is the "PayPal Express" button and it's nice for customers because it allows you to bypass
filling in your name and other info on the website.
Unfortunately, sometimes the PayPal site returns and error from the "Express" process and the button doesn't work. So far, none of the tech support team can tell me why that happens.
Fortunately, you can still use PayPal when buying designs. All you do is fill out the normal customer info page and when you get down to the area where you fill in your credit card info, just click on the PayPal button instead. That takes you through the normal ( vs "express" ) PayPal system and so far it always works.