Follow these steps so that you can have a trouble free running version of Windows 8 Developer Preview:

Configuring Oracle VirtualBox for Windows 8 - 42Configuring Oracle VirtualBox for Windows 8 - 3Configuring Oracle VirtualBox for Windows 8 - 78Configuring Oracle VirtualBox for Windows 8 - 42Configuring Oracle VirtualBox for Windows 8 - 60Configuring Oracle VirtualBox for Windows 8 - 13Configuring Oracle VirtualBox for Windows 8 - 26