After some testing, I’ve realized that the motherboard I’m using, Intel D945GCCR can’t simply boot from img files when burned to usb. It boots from the same usb stick and even the same usb port using Debian, Ubuntu or Windows images, no issues there at all, but Batocera, Lakka nor Recalbox all of them fail to load, the motherboard simply skips the usb device as a valid booteable one. The only difference between those working and those that are not, is that the first list are burned from ISO files and the second list is burned from IMG files. Tested both batocera x64 any x86, all of them are simply skipped, updated the motherboard to latest valid bios version, downloaded older versions, so the problem seems to be on the content of the img file itself to boot and/or the content against what the motherboard expects to boot.
Any ideas on how to get through this?