Hello Rob/PE1CHL
I use very SUCCESSFULLY JNOS-2.0k compiled on Debian-8-7 and Debian-7.11 both 32 and 64 bit as native on HDD and in VirtualBox as well.
I do not see ANY issues on mentioned systems. I compiled JNOS-2.0k on Fedora-24/25 too, also successfully running later on.
Best regards.