@mfalkvidd sure....
I just took the example EnergeMeterPulseSensor.ino compiled and flashed it. It looked to work at some amount.
But when I have the sensor on an analog input rather a digital input I had to do some changes. So when I was to download the changed version at the first time it wasn't possible. It failed. So after some tries I reflashed the bootloader. And now I could download again
But only once.... Then it failed again. So reflash the bootloader again and it worked.. once....
So after some tries I removed the MySensor.h include and comment out all the related errors after now I could upload multiple times. So I guess there is some code that writing at wrong registers or similar.

Some other notes..
When I don't have any radio I removed MY_RADIO_xxxx. I know I tried to set the MY_GATEWAY_SERIAL but no success.
But please note that I don't remember every detail I did but I tried some different configurations but not any worked. All ended in destroyed bootloader.

So I did my own message creation functions according to the API but the controller don't want to accept it fully and therefore this questions about the communication protocol sequence..