Did a clean install of the beta, and then a config restore from a 7.4 backup. Everything in Webadmin looked fine, showing the cable modem connection was up, etc - but none of the client PCs in my home could get to the internet. Checked (and renewed) IP Config on a few clients -- all had received the correct IP and DNS info from the Astaro (using internal DHCP) but could not connect outside.
Finally did another restart of the Astaro and it started working again - figured you might want to check the restore process in 7.450 and see if there is a hiccup there (or if others are seeing similar).