"Is it possible to work without being connected to the internet?

I know nothing about pyradmon, but there is an entire section of the forum dedicated to it, here:  https://radmon.org/index.php/forum/pyradmon . You may find an answer there. If you are using Python 3, then you could try using Py3Radmon.py from this thread here:  https://radmon.org/index.php/forum/pyradmon/1268-python3-support-for-pyradmon . It may, or may not fix your issue.

Try connecting your counter to a stereo or HiFi, or something with a AUX input. you should be able to hear the clicks from the counter with the speakers if it is working properly. Also, make sure the jumper (P100) is fitted as that is required for the audio output according to the circuit diagram.

I have also noticed a discrepancy in the circuit diagram, or I should say, diagrams. Seems there is more than one circuit diagram available for the CAJOE and of the two I have looked at, one has the pulse audio going to just one of the stereo channels, and the other diagram has both left and right connected for pulse audio. It is possible the pulse audio is just coming from one channel and the software may need the other channel. I will have a look at my CAJOE when I get home later today and see if both channels or just one is connected.

I have attached both circuit diagrams below. You can see that one has both audio channels connected, but the other just has one channel connected. If you could plug your counter into a stereo it would be easy to hear if the clicks are just coming out of one speaker.

I have just checked my CAJOE and both audio channels are linked together. Best I can suggest for now is try and connect it to a stereo or something and make sure you can hear the clicks from the speakers.