Alright, here's my dilemma. I'm trying to boot up Niresh Mavericks on an AMD64 desktop (I'm not using Yosemite because it takes 5 minutes to load all the HFS+ files on that one). I've gotten stopped by the infamous "PCI Configuration Begin" hang, and I can't fix it; I've tried pretty much every combination of PCIRootUID=0/1, npci=0x2000/0x3000, pci=no, GraphicsEnabler=Yes, dart=0, -x, and so on with both /amd and /amd64 (this is not an FX system); no luck on any try. I finally found some custom kexts somebody made that are supposed to be able to bypass this. I know they go in the Extra\Extensions folder. But here's where things get tricky;
The computer's motherboard doesn't support booting from a USB drive, so I have it burned to a DVDR-DL that I'm booting from; I've got like 50 of these laying around, so I've no worries about burning more. Of course, this means I'm using the ISO file, which can't be edited; only extracted, edited, and then put back together. Problem is, I can't for the life of me get it put back together properly. I'm using PowerISO, although I do also have IMGBurn and Image Master at my disposal. What I've been doing is taking the ISO, backing up the boot information, extracting it, manually extracting the [BOOT] folder with 7zip, putting it back in, adding the kexts, and then putting them all back into PowerISO, making it bootable, and using the boot information from the official ISO. It does create a valid ISO file, but it doesn't actually boot; it just hangs on the boot screen (I've been using VirtualBox to test it, where the normal ISO works fine).
To make matters worse, I can't browse the filesystem contents of the disc on my Windows computer, so I can't just edit it directly that way (haven't tried on Linux yet, but I'd assume it's no different). I do have a Mac Mini available, but it has no disc drive, and I don't have any external disc drives to hook up to it. I need some way to add custom kexts to the Niresh ISO file, and still be able to burn it to a disc and have it work.