Also tried with VirtualBox. [...] Runs fine up to "The len of the gambit file is: 9569 520" but then hangs at full CPU usage.
Wait, everything does work in VirtualBox too. It just takes several minutes to load the gambit file. After that it's about as fast as with QEmu; even the interpreted fibonacci runs quickly. Maybe the load time is due to some difference with the way interrupts are done in VBox or which kind of IDE disk it is emulating?