HP 8300 add unable to flash modded BIOS

[Groupers]

I have an HP Compaq Elite 8300 SFF desktop and I'm trying to add the PCIe AHCI driver for my Samsung SM951 SSD. I was able to add the driver with mmtool but now I can't flash it.

Here is the original update package for my BIOS ver from HP http://ftp.hp.com/pub/softpaq/sp77501-78000/sp77888.exe

Is there any way to get a modded version of the included HPQFlash 4.40.1.1? I have 4.30.10.2 and have created a ROM.CAB but it doesn't recognize my mainboard, so it won't flash.

The BIOS image is not compatible with this system.

Family of BIOS in ROM update: K01
Family of BIOS in system:

The system BIOS will not be updated.

Is there any other method to flash a modded BIOS that may work? I tried dumping my BIOS with FPTw64 8.0.10.1464 but it tells me this.

Error 26: The host CPU does not have read access to the target flash area. To enable read access for this operation you must modify the descriptor settings to give host access to this region.

I was afraid to blindly flash with fptw, thinking I might end up with a brick. Any suggestions would be greatly appreciated.

[Groupers]

It turns out my bootloader was the issue. I am now able to get all the way through flashing, but as soon as it's done with block 4096 of 4096 I get a different error message that's related to WMI. I haven't been able to confirm whether or not the BIOS flash is actually taking. The machine reboots and I've cleared the CMOS, but the SM941 still isn't directly bootable, nor does it show up at all as a disk.

I will post more details soon, along with a link to my modded BIOS, if someone could take a look at it. Perhaps I've just made a mistake.

[Groupers]

Here's the error message from HPQFlash.

An unrecoverable error has occurred while flashing the BIOS.

Error code = 0x13 (FLASH_IN_PROGRESS_WMI).

Then it says "The system BIOS has NOT been updated."

Now, after a reboot it will not POST. After clearing CMOS it appears to POST. It beeps, Numlock light turns on/off, CTRL-ALT-DELETE restarts it but there is no video output on the VGA port at all. Any ideas?