Just tried the COWOA mod out on my test site www.nps1direct.com/zcf and it works fine using ZenCart v1.38.

After creating an order and going through the whole process, I decided to try again to see what would happen as a repeat customer who used the Checkout without Account step. I found the following problem after filling in the Billing Information page:

"Our system already has a record of that email address - please try logging in with that email address. If you do not use that address any longer you can correct it in the My Account area."

When I click on the link in the "If you have an account with us, you may login at the Login Page." sentence I received the following error:
"Error: Sorry, there is no match for that email address and/or password."

Is there a way to get rid of this so the customer can continue onward?