I am afraid that I am still unable to reproduce the problem at hand. Indeed, the inner properties of RadCaptcha are added when inserting the control from the Visual Studio toolbox into a Wizard step, however there are no errors in the build on my end as you can check in the following screen capture: http://screencast.com/t/oiPEqeWbhyF
Please check the linked video and let me know if there are differences in the setup of your project. For example, is your project a web site as well, is there something different in the settings that are visible in the clip, are there differences in the configuration of the page and the controls?
This information, in addition to step-by-step instructions for reproducing the problem (you can also use a video for this purpose), will be very useful for recreating your scenario and determining what is causing the issue.
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