Yeah, I seem to remember that, too. Considering how quickly it sucked up RAM, I'd say their system probably had a hardware problem (bad RAM will do that) or they were doing something insane like running it under Windows 98.
That's one thing that 9.mzx never did for me was annihilate my system. All it did on my computers was to keep eating RAM until Windows finally said, "ah hell naw" and killed it.
In a way, despite how amused I was with the finished product, I sort of wish that it did work as intended. Alexis even gave me a few pointers about the intricacies of how MegaZeux stores boards. You see, it's all her fault. :p
The wave of MZX "viruses" that followed it were a little annoying, though.