I'm using jaws 15x and have win 7. In the last couple of weeks, the "proceed to checkout" button has become unusable. Very annoying but, it's apparently not just a win 8.1 problem.
If I remember right, though, you can put things into the shopping cart from the access site but when you're ready to check out, it takes you to the main site. Hopefully, they'll get this fixed. karen For answers to frequently asked questions about this list visit: http://www.jaws-users.com/help/