Windows 10 update breaks my CAD software - rolling back update breaks system boot, how to roll back update?

I'm on Win10 Home x64

I was sure I had disabled windows 10 updates with extreme prejudice (via registry and group policy editor), but I came in to work the other day and found that Windows had somehow updated anyway.

It's installed Security update KB4093112, update KB4134661 and Security Update for Adobe Flash Player (doesn't have a KB number but if I highlight it it says the support link is for kbid 4013729). Since the update, when I use my CAD software (Missler TopSolid), it crashes when I open a particular screen. I've tried to debug it using Visual Studio but I only have a version with an expired trial license. I can see that the error is:

"Unhandled exception at [mem address] (nvoglv64.dll) in top.exe: 0xC000041D: An unhandled exception was encountered during a user callback."

Now as I said it's a trial version of Visual Studio so I can't delve into this anymore, but I know that the dll in question is part of the NVidia graphics drivers. As such I've tried downloading the latest version of my graphics card drivers and I've done a clean install (erasing previous files/settings) but that hasn't solved it. Either way it never did this before the windows update so I don't think the driver itself is the problem.

I've tried going to the windows update manager and removing the updates in question but windows then fails to boot. It'll try a couple of times and then go to startup repair, which fails and gives me a path to a log file which as far as I can tell isn't actually there.

I've figured out that in order to get windows to be bootable again I need to go to command prompt and use DISM to revert pending actions... but all that does is get me back to windows with the problem updates installed.

I've also tried using SFC which completed successfully without finding any problems, and from the command prompt I've tried using bootrec and bcdedit to rebuild the MBR and such but it can't find my windows installations.

So basically all I want is either some ideas on how I might go about fixing the error with the nvidia driver DLL (bearing in mind I've already reinstalled drivers) OR how to roll back and permanently disable the windows updates in question (I suspect it's the KB4134661 one that's doing it) without borking my windows install. I would strongly prefer not to have to reinstall windows because I have specialist and legacy CAD/CAM software which is a complete pig to set up.

I don't have a restore point etc. from before the updates were installed because although I thought I had it set up to automatically create them, it hasn't.

Edit: I am NOT asking how to stop updates as I already know the different ways of doing that, it's about how to stop windows boot from breaking when I uninstall some updates that have already been installed.

Second Edit: I've now tried rolling back my NVidia drivers to 385.28 which is from August last year and I'm still getting the same problem.