Thanks for all the suggestions but I'm afraid I'm still going nowhere here.
ZacharyBruno:
What about the Serial.print lines? If you remove all those, does the program work?
Nope that didn't work.
This I have to research more if I should go ahead and do. So I'll put this on hold if the next one is simpler.
dc42:
...or convert the data directly from 'buf' instead of copying it to Sensor1CharMsg.
I tried this but that didn't work. Allthough I doubt I did it right. Am I looking for a char to integer converter or something else?
Sensor1Data = atoi(buf);
Error Message
conversion from 'uint8_t*' to 'const char*'
rgb_mixer_RF_controlled_pulse_makkan_v4_ino:115: error: initializing argument 1 of 'int atoi(const char*)'