Paypal Custom Style Page - where to point?

I already have created a Custom Style Page in Paypal for my store, and i am wondering where i should insert the code so that my customers to THAT store will see THAT custom page?

When i create a Paypal button on another site, there is the variable ps="paypal" using the default Paypal page, and i could replace that variable with the name of the specific style i created, but in zen, where is that variable set or used?

Should be settable in the
admin > modules > payment >

Where it asks

PayPal Page Style
The page-layout style you want customers to see when they visit the PayPal site. You can configure your Custom Page Styles in your PayPal Profile settings. This value is case-sensitive.

Thank you. It was well hidden from view. It seems to be exactly what was needed.