@renewedharry While I can’t give you a solid answer with your issue, but someone else on the forums had an issue just recently with this software that you might be able to start from: https://forums.fogproject.org/topic/17124/i-can-t-boot-up-parted-magic-2023-08-22/2
For a mixed environment where you have bios and uefi computers, they take different bootloaders to successfully boot. Being on version 0.3 may be hurting your knowledge if FOG since SO MUCH has changed since that version was released. For bios/uefi coexistence you might want to review this wiki page. https://wiki.fogproject.org/wiki/index.php/BIOS_and_UEFI_Co-Existence