Faking CPU in VirtualBox: CPUM internal processing error #1. (VERR_CPUM_IPE_1)

I need to fake a CPUID to revive a legacy system. I managed to get the dump of cpu registers and used vboxmanage modifyvm VMNAME -cpuidset num eax ebx ecx edx The VM breaks and returns this following message:

CPUM internal processing error #1. (VERR_CPUM_IPE_1).

Exit code:E_FAIL (0x80004005) Component: ConsoleWrap Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

Any clue about how can I make the VM start with the new processor? I tried modifying the CPU in an existing machine and it did this, then I tried to make a new machine from scratch and launch it after CPUID modify. Thanks in advance guys