[syslinux] New UEFI restrictions?

[eas lab]

Previously I've been using a laptop with an "Aptio Setup Utility...2015"
to "Disable UEFI Boot" and allow a USBstik with partition1 having:
  /boot/isolinux/isolinux.bin , isolinux.cfg , menu.c32...etc.
 to boot 64bit TinyCore.

Now this newer laptop has: "Aptio Setup Utility...2018"
which is completely different from the 2015 version.

I fail to boot linux from any of my various syslinux/grub bootStiks.
Has M$pook finally locked linux out of <WinTel> laptops?
Or have readers here got a solution?

=TIA crg.