recaptcha custom implementation

I am using the recaptcha plugin from google and I need to make a custom implementation. I want to create some sort of wrapper around this control so that I can embed my private/public keys in addition to setting a theme. I dont want my consumers to be able to modify any of these settings. This control/wrapper will then be exposed to the rest of my enterprise as a plugin from within their asp.net applications. I know I can create another class and inherit from the recaptcha class and set the private/public key that way, but when I reference the class library from an external web application its saying that I need to add a reference to the google recaptcha library in my web project. I would assume it would already be embedded in my class library. Can someone advise on the proper method to accomplish what I need or advise on an alternative method but still using the google recaptcha plugin.

Thanks