Hi, my good friend.
I will share here my experiences in this subject:
Usually integrate OEM drivers that are MS certified, using Dism works fine in almost all scenarios. Just remember Dism only integrate the divers in text mode, using the info in the *.inf file.
Certain drivers also create some services by the respective entries in the Registry, and even if they seem to integrate fine using Dism, they don't work fine, because the services required to start them don't exists.
Some samples of OFFLINE integrating problematic drivers are:
wofadk.sys (MS driver from ADK, obviously certified):
In this case you need to also find the additions that are made to the Registry during a real installation in online OS made during first run of WinNTSetup, I will not waste your time talking about this. as I'm aware you alredy know very well how to do this.
Then after just copy the driver to its respective location, it is just a matter to integrate the additions to the Registry by means of your well known offlinereg by erwan.l, (just remember to DO NOT use a *.reg file made by exporting it from the Registry, better copy its content to a new file in Notepad and save it as a new *.reg file, if not the procedure DOES NOT work fine).
diskmod and SvBus. (Not certified by MS)
The issues start when you want to integrate drivers that are not MS certified. In this case you need to first integrate in the Registry the (Local, User of modded) Certificate, and after this integrate the driver with Dism and also the *.reg files for additions to the Registry (if any) with offlinereg.
Also it is a good practice (usually a requirement) to enable Test Mode (testsigning) in both BCDs (MBR and UEFI) and Disable Integrity Checks in both BCDs (MBR and UEFI), please see attached photo.
NOTE: I have noticed BootIce is not capable to create good working entries in BCDs for WinPE.wim files based on Win10 and newer, (it seems to me this issue is related to the OS GUID required for WinPE.wim files based on Win10 and higher as once the entry exists, it is able to make modifications to it), so I only used it to show the content of the UEFI BCD store, but it works very fine in case of Win10 and newer OS installed in VHD or real hardware.
I can confirm previous procedures work fine without any doubt upto Win10 2004 inclusive, but on newer Win10 versions or Win11 the Requirements for Integrity Checks and Drivers Certification were increased, so in case of Ramboot VHDs, it is neccesary to also Pre-Load first, (before boot) EfiGuardDxe.efi, (link to its page in GitHub), to let this new OS versions load SVBus driver without any complain, if not the user is forced every boot to press the F8 KEY for Advanced menu and Select Disable driver signature enforcement, to allow load unsigned drivers.
alacran