I have created a udev rule as you suggest. Trying to connect generates a different error.
Trying to connect from Kstars generates the following...
2019-05-18T15:47:31: [ERROR] Failed to connect to port (/dev/NEQ6). Error: Port failure Error: Inappropriate ioctl for device. Check if device is connected to this port.
After a restart, if I enter ls -l /dev/NEQ6 in the terminal I get
lrwxrwxrwx 1 root root 15 May 18 16:38 /dev/NEQ6 -> bus/usb/001/008