Captive portal Openwrt firmware project

Hi There, I'm looking for someone with experience in building captive portals, in particular a firmware option to be installed on routers that forces the user to log in with either Facebook, Twitter, Yahoo or Google before they can access the Internet. We have been trying to use Coova but cannot get it to work exactly how we want it to work. I am interested in hearing from anyone who has experience in this and can offer a solution. Ongoing work available if we can make it work. Cheers Greg