So I installed the module and added it to my Comments form. I have tested Image Captcha and Math Captcha, both when logged out, just refreshes the page when you submit. No warnings, errors, nothing. You just get your comment form with all the stuff you entered and a new captcha.
I have tried opening up comments to skip approval process, no good. Have cleared cache, no good. Am I missing something? Perhaps the Beta2 is the wrong one to be using and I should use the dev?