Huion 1409 V2 problems

Hi all,

I'm using a Huion WH1409 V2 tablet, which is proving to be very glitchy. At the moment, al that happens is that the cursor moves around the screen, but I'm unable to select anything, and cannot work with any applications.

I'm on an iMac running Mojave 10.14.6

Also using the latest driver for this tablet.

Any clues about how to make it work?