@CaseySJ
For the last few days, with AptioMemoryFix / EmuVariableUefi and VirtualSMC , I have been able to boot and shutdown without errors. I think we do have a promising alternative to free2000. The only thing that I can't do is to enable SIP.
Last night I tried to enable SIP following the process to disable MSR 0xE2 and enabling SIP worked. I haven't observed the stability for long. Will do and report back,
Nevertheless AptioMemoryFix / EmuVariableUefi and VirtualSMC are stable alternatives to free2000