Desktop Video doesn't recognize Intensity Pro 4K

I've worked with an Intensity Pro 4K-card for a year without any problem, with the 10.9.3 version of Desktop Video. Now I upgraded my edititing system to Avid Media Composer 2018.7.1, and alas, it won't accept such an old driver for the I/O. It must be 10.9.10 or newer. But when I update, first to 10.11, then to 10.10 and then to the minimum 10.9.10 I get the same disturbing result from Desktop Video: "No desktop video device detected." I reinstalled the 10.9.3 version, and it still works just fine - but not with the editing software.

So I'm sort of in a limbo. Is there any way around this?

I've had the same problem - but it was in Windows 10

viewtopic.php?f=21&t=72340

Thank you very much, Ole! A simple, beautiful and working solution!