Hi Eric,
I just tried to re-produce this issue on my test portal but I wasn't able to recreate the same behavior, the State/Region field was populated correctly whether the transaction was failed or successful. Are any errors being logged to your DNN Event Viewer?
I may also not have the exact same configuration as you so I would like to have you login to one of our public test portals and configure the cart the way you have your's configured and try to replicate the issue. This will determine if the issue you are reporting is with the latest version of the cart or an issue with your specific DNN portal/cart install.
Please submit a Ticket with a link to this post to our HelpDesk at the following link and I will provide you with credentials to login.
Click here to submit a Ticket
Thanks!