Neat scanner ND1000 with Big Sur
I tried the suggestions of other posters about downloading the latest scanner driver (4.0.1) from the Neat website and installing it. I had to take an extra step to make it work.
After making sure I had the latest version of the Neat Scan Utility (1.5.2) in my Applications folder, and the latest Neat scanner driver (4.0.1), I still couldn't get my iMac or the Neat Scan Utility to find the scanner. My solution was to open System Preferences > Printers and Scanners and click the "+" sign to add the Neat scanner. After that, everything worked perfectly! I've tested the Neat scanner with the native Mac scanner app, the Neat Scan Utility, and PDFScanner (from the Mac App Store). So far, so good.
Good luck to all!
iMac 27″, macOS 11.6