Doesn't really look like many people are around here to offer support, but here is an update just in case.
I managed to get some access to the HDD by booting up with a Windows recovery disk inn the DVD drive. At first this would not work, and gave a message "This version of system recovery options is not compatible with the version of windows you are trying to repair". After a bit of internet investigation I brought up the boot choice on bootup to find there were two entries for the DVD drive, one preceded by UEFI. The windows recovery disk would then fire up. Windows startup repair did not, of course, work. Neither did a system restore (but I did not expect it to really).
I got access to the command prompt and was able to establish that my HDD had not failed, neither was it obviously corrupted. All my files were present and I was able to back up the more recent work since my last backup to a usb stick. So I am secure that I have all my files, which is more than anyone else in this position.
I daresay I could now manage to reinstalll windows, but I am not sure that would solve the problem. I am now convinced the issue is in the bios settings. I reflashed back up to F22 to root around again in the boot order etc, settings. UEFI MyHDDname is number one. Then my DVD drive, then USB. I disable the last which was showing PO MyHDDname, as this does not work. I made sure SATA was set to AHCI.
And, I am still in the same position, unchanged. Power on the machine, bios splash screen, then it powers off and restarts, bios splash screen, then windows splash screen, then to startup repair wich as I already know from many tries, does not work.
Are there any other SATA or boot settings I should change? It just seems to be an issue of bring the bios into the right state to set my HDD into proper boot up motion.
Len