Thank you Tito for your answer! I did send an email to the support in Belgium about this problem. Today, i did get an email back from them together with an .ROM file. Version of ROM stay the same but they have made the option Secure boot visible. No explanation or anything, just how i install the firmware and that it now should be visible. Now i clearly see option in Bios; Secure Boot; Enabled/Disabled. But the trick you say i try out before bios update; and it worked! Thanks for your advice, also thanks from my sister to you! But why it not worked earlier with an DVD? And also thanks to the support from them that did bother to answer me.
For me using the UEFI option saved me a lot of time once. I had set my mainboard to the boot setting: "start superfast" (few seconds from 0-desktop on a hdd). But i wasn't able to press f1/del in time to enter the bios anymore. Using the boot-to-re script from Murphy78 I was able to go to the UEFI bootsettings and it enabled me to reset the bootsetting to "normal boot", so sometimes the use of UEFI boot can be helpfull (i did never see the option for bios/legacy boot in the winre environment). UEFI booting is also available for win 8.x and up x86 but only on x86 UEFI bootable systems. ps, there is no need for the use of rufus for creating a UFD, just format the usb thumbdrive FAT32 and unpack the iso to it (when the install.wim is larger than 4GB you either can split it in swm files (under 4GB a piece) or compress it to install.esd format).