[pshoey]

Making NBT accept a custom set of FSCs is trivial - just patch in the new root certificate and voila. But I agree, X86 makes it a little easier.

And yes, for a complete solution, understanding what the classic FSC extension data is used for and generating genuine data is an interesting intellectual challenge - if only I didn't need to sleep!!

As the extension data appears to be ignored by the HU, and @aknight720 says it is RSA encrypted, maybe the data is signed by the sig cert - which I have not found a use for previously. I'm not sure how @aknight720 has decrypted the data - presumably the private key is in the HU binary?? That would mean the sig cert is not used (unless the private key for that is in the binary, which I doubt). Of course the sig cert public key can be used to verify the extention data has not been tampered with but then the MD5 hash inside isn't a great deal of use!

I'm sure it will all become clear.