I'm looking to introduce CAPTCHA support on key form pages, such as creating forum posts, registering users and posting comments. I've seen discussions about this with regard to adding controls directly to the core files (e.g., CreateUser.aspx). I'd prefer to handle this via widgets, however. I'd also prefer to avoid forking existing widgets, if possible, since the Velocity script for widgets such as "User - Login and Create" is fairly involved.
Does anyone have any best practices or guidance with regard to creating widgets that can integrate with forms? E.g., Can widgets participate in form processing, similar to how Subforms worked in Community Server? I'm not seeing anything, but I want to make sure I'm not missing something.