In my experience for that problem is.. it's the same as you cant update centos even you're internet connected or can browse internet. I used Centos 5.1 from thoughtpolice.co.uk but i update it once only, i dont know why. Also getting the error the same as yours.."could not retrieve mirrorlist...blah..blah..".So i tried to download Centos 5.2 but still the same, you can update it one time only. So you have to make backup or copy of your updated vm centos(*.rpm already installed)
before copying the other server files to your vm centos, so incase you want to start making cabal server again for any reason you dont have to return to that problem anymore. Now in order to solve your problem.. use the proxy server of Centos.Go to system,preferences,network proxy and fill in http proxy with the proxy that works for you. "ex. 58.253.71.248 port:80". then check if you still have internet connection with Centos, if still have then update it or go to terminal and go on with your "yum install... blah blah...".
sorry for my bad english..