we are still looking into this. Currently we’re preparing for 4.0.44 which might solve it, but still chasing a crash bug only on certain machines that are not within our reach 
I had a very similar problem myself, it was a damaged vstconnect.dll.
In my Nuendo 10 folder there ist a components/vstconnect.dll file. However as you already suspected, afaik the commonfiles version should override local versions. Nevertheless you might try: a) copy the common (4.0.43) one to nuendo/components, if that fails, try the Cubase one. If nothing works don’t forget to remove it again.
Does your Cubase work with VST Connect?