Quote Originally Posted by linuxguy2 View Post
archelaus
On the OPC admin page if you have "Enable One-Page Checkout Debug? Full" you should be getting PHP notices/errors in the Logs. (Two places System root / and your cart root.)
You may already be aware of this but OPC is being update. You might review some of the latest unreleased fixes for 1.5.6a noted here.
https://github.com/lat9/one_page_checkout
Thanks, linuxguy2!