Address not being accepted

I can enter an address (user registration) once during checkout and it will be accepted. But if I return to order another product on the website later in the day it will not accept any address I enter. I'm not requiring registration. This is the error I get. "Please create or select an address" I enter an address and it returns this error message like I didn't add one. This just started happening after I altered the checkout process by adding a "," instead of a "_" between certain fields. I never could get the checkout to continue on to PayPal after doing this. It would just say your order has been processed, but there was no redirect to PayPal. So I pasted the default checkout flow back into the dialog box. Then this problem started, even though I have the default checkout order back in place.

I'm testing on a Mac platform. I get this problem in FIrefox and Safari, but I have not been able to replicate it in Chrome.

Also during the checkout, I have to click the next button twice to go to the "end section"

I just updated to the current version today again since I saw some modifications listed in the forum. I had just updated to 1.4.5 last week to fix the click next button problem.

URL abetsolar.com/index.php/products/s4000-model