How do I add a coupon alert via messageStack for COWAO?

Hi all,
I have a question about the messageStack. I created a coupon for the new signups, it works great but am also using COWOA module and customers who do not register do not see this coupon. So I am trying to implement a messageStack to show it. But unfortunately there is not much info on it, so I don't know how to get it done. What I want is when a customer fills out a form on the "no_account" page and if he gets transferred to the next page("checkout_shipping") to show the messageStack with coupon info on it. I have already tried to do it like in contact_us but it does not work.
Any help is appreciated!!!

Well, at least can somebody give me some info on messageStack or where I can find it?
Thank you

If you created the coupon specifically for the new signups, I would think you want to reserve the coupon as a reward for those that actually signup?

Anyhow, if you want to offer it to everyone, how about placing it in the header of your site? Many ecommerce sites use this placement to entice visitors to put items in their cart. If they don't know they'll get a deal, they may not buy anything in the first place.