I have reset and check my BIOS as suggested.Not sure I can help but for what it's worth ...
First up check that your BIOS hasn't reset itself to defaults. This used to be a common occurence a while back and there was a MultiBeast fix in place to prevent it. Personally I've not had a BIOS reset for a very long time but it's worth double-checking.
Next, do you still have a Sierra UniBeast installer stick? If so use it to re-install the previous version of Sierra it was created with. Don't boot to the installed OS, instead boot to the External disk, i.e. the installer on your memory stick etc. It may give an error if you try to install (in the past you weren't allowed to rollback) but again, for me, it worked fine and allowed me to re-install 10.12.3. Because the disk wasn't formatted afresh it left all my apps and data in place and just rolled-back to 10.12.3. Took about 30-mins. Once there I was able to update Clover before trying 10.12.4 again. Give it a try?
I would normally say back up your data, but perhaps you can't get at it? If so try attaching the SSD to a Windows system using an HFS+ driver to copy it to safety.
You might want to take a look at the packet filter and it's configuration fileWhen rebooting, I temporarily set iMac 14.2 to boot and then the serial number of the company changed which was already lit up in my Icloud, after installing the patch on the video, my system booted up as IMac 17.1
The simplest mechanism to block everything by default and only pass packets that match explicit rules is specify a first filter rule of:
^ type ^ chipset ^ kext ^ product ^ |MOTHERBOARD: | X58 | FakeSMC.kex | GIGABYTE GA-X58A-UD3R | |BIOS Version: | FH | | GIGABYTE GA-X58A-UD3R | |CPU: | Socket LGA1366 i7 | NullCPUPowerManagement.kext | INTEL i7 950 3.06GHz | |LAN: | REALTEK RTL8111E | RealtekRTL8111.kext | GIGABYTE GA-X58A-UD3R | |AUDIO: | REALTEK ALC889 | AppleALC.kext, VoodooHDA.kext | GIGABYTE GA-X58A-UD3R | |GFX: | NVIDIA GeForce GTX 760 | (ootb) | EVA nvidia GeForce GTX 760 | |SATA south: | INTEL ICH10R | | GIGABYTE GA-X58A-UD3R | |SATA north: | MARVELL 9128 | AHCI_3rdParty_SATA.kext | GIGABYTE GA-X58A-UD3R | |eSATA: | JMICRON JMB362 | | GIGABYTE GA-X58A-UD3R | |USB 1.2/2.0 south: | INTEL ICH10R | | GIGABYTE GA-X58A-UD3R | |USB 2.0/3.0 north: | NEC uPD720200 | GenericUSBXHCI.kext | GIGABYTE GA-X58A-UD3R | |USB 3.0 PCIe: | Fresco Logic FL1100 | (ootb via AppleUSBXHCI ) | Inateck KT4006 | |FIREWIRE: | TI TSB43AB23 | | GIGABYTE GA-X58A-UD3R | |FIREWIRE PCIe: | TI XIO2213B | | Digitus Firewire 800 / 400 Combo, DS-30203-1 | |BLUETOOTH: | BCM20702 | | GMYLE USB Broadcom BCM20702 Class 2 Bluetooth V4.0+EDR | |RAM: | 32GB DDR3 1600MHz CL9 | | HyperX Savage HX316C9SRK4/32 32GB (1600MHz, CL9) DDR3-RAM Kit (4x8GB) |