Files not inverting at all - Lightroom Classic 11.0.1, M1 Macbook Pro '21

Hi there!
I’m a new user who’s been experimenting with scanning with my Nikon D850 after years of using a dedicated PlusTek film scanner.
I’ve been trying out Negative Lab Pro on my M1 Macbook Pro (Mac OS Monterey 12.0.1) on Lightroom Classic 11.0.1, and I can’t get it to work at all…
Regardless of whether I use NEF files from my Nikon, or Tiff files from VueScan, NLP simply won’t invert my files at all, no matter what settings I use.
Any ideas what might be going on?
Big thanks in advanced!

Click on the CONVERT NEGATIVES button. Hitting Enter does not start the conversion.