After few days of debugging I didn't go any where, I decided to reinstall Beta 2 again from scratch, this time I captured all the console output to a file at the same time I monitored the output on the screen, amazing no errors from the installation, and when I run the postinstall script it installed nvidia latest driver, and everything came up without any issues.
I suggest for new installation to capture the installation log, and check if there is any signifcant errors, if yes, restart the installation process over again maybe in a day or 2, possible some servers are down.