Sorry for long response.
I'm using PTP, writing in C#.
Unfortunatley, despite chdkptp is far developed and has all functionality I am trying to implement, it is hard for me to understand it's sources (I've already tried and that lua part is kinda tricky for me) also I need to make my solusion in C# using nothing but it.
Fourtunatly I've found project :
https://github.com/chakphanu/CHDKPTPRemote - it helped me a lot and it fulfills my question.
May I ask you one offtopic question? How could I transfer photo to PC?
Via PTP as I understood... But I wasn't been able to find nor any documentation nor any usage examples of it.
Thank you very much for taking your time.