I had the same symptoms. Try the changes to the code I made in pull request 95. It uses a newer Linux API to register the device, and libinput seems happy with it now, so it works in gimp and inkscape.
CPU not detecting tablet
I’m not sure what I’m doing wrong. I installed the driver, ran all the correct codes and got the confirmation which states “GFXtablet driver (protocol 1) is listening on XXXXX (udp), Hint: Make sure this port is not blocked by your firewall” and I kept that terminal open. I installed the app directly from google play store and then I typed in my IP address. It didn’t pop up with an error code or anything. I then opened gimp and set my input to “network tablet”. It all seems like it was done correctly but the computer doesn’t even seem to detect my tablet, as when I draw on it it does nothing. Everything is default unless I specified otherwise. Any/all help would be appreciated.
It seems you didn’t run the networktablet executable in a linux terminal. You need to start this and leave the terminal open. Only then you’ll get a connection between tablet and you operating system.