You may have noticed that your FlashRouter's WPS button is not working. This automatically is disabled once your router is flashed to DD-WRT or Tomato firmware. The WPS button is a known vulnerability of stock firmware that allows hackers easier access to your network. You can read more about it here.
As soon as we flash your router to DD-WRT or Tomato firmware this feature is disabled making you that much more secure from outside threats. For a full look at this you can check out our FlashRouters Blog post regarding WPS.