problem with UEFI install on Sony Vaio Pro 13 w/Windows-8.1

My colleague and I went with the default ‘as delivered’ firmware settings in their Sony Vaio Pro 13. The only parameter we toggled back and forth a few times was the ‘secure boot’ parameter, when we first encountered the Windows8 boot problem, to ensure the ‘secure boot’ did not cause the problem. I do not have access to their Sony, so I can not comment further on any Firmware settings.