Okay, I am now one step further. Following your plan, and testing a script from the command prompt gives this error output:
error: host not found
Traceback (most recent call last):
File "TestON.py", line 3, in <module>
f = Fritzl('MyFritzboxPassword')
File "/home/pi/domoticz/scripts/fritz ...

Okay, I am now one step further. Following your plan, and testing a script from the command prompt gives this error output:
error: host not found
Traceback (most recent call last):
File "TestON.py", line 3, in <module>
f = Fritzl('MyFritzboxPassword')
File "/home/pi/domoticz/scripts/fritz/fritzl ...

Do you have python installed? If you do test the scripts by running from the command prompt.
I must admit that I had not installed python. :oops: A real beginner error. :oops: :oops: My apologies.

I have now installed it (sudo apt-get install python), and it looks like this installed version 2.7 ...

So, I am kind of stuck with this to work, and I would need some advise.

I have a Fritz!Box 7490 with two DECT200 switches that I would like to use with Domoticz (because we can :) ). I am on Domoticz beta V2.2539 on a Raspberry Pi B.

I followed richardh's step-by-step plan, made a script for "On ...

I think the device brick turns yellow when the battery level is low (you will also see "low" in the device list), but it won't show a percentage. Would be nice though...