It's an "old" nvidia card you have. You have to rely on the open source driver that Zorin uses as default for your card. If you're not a gamer this should not be a problem.
In that case you might want to try installing the driver manually. Go to nvidia page and find the latest driver your card is supported by and follow this guide;
There are a lot of alternatives in Linux that will do everything that Blackmagic 's free linux version does including much more then the paid version does and cost nothing. Blackmagic products have issues even in M$.
I speak from experience. What is it that you need that is exclusive to that software ? (i.e. video editing, color grading, audio post, and video effects to help editors, or sound assist ) KDElive which is probably the best or Blender which is included in Zorin 16 Pro. (Many a Hollywood movie has been made with it)
I will start to edit my videos and DaVinci seems promising. I need to have some kind of color correction. I've installed DaVinci but it just doesn't fit my screen (1366x768) I can only see the half of the interface only. So most probably I will try Kdenlive.