First, Thanks for your response  (I always have used your tips and hints on this forum in the past)
I’m sure that it’s happened as you said, but I don’t know how it’s possible… anyway I will try to format and redo from beginning.
In any case, which is the best walkthrough could you suggest to help me with my build_and_compile problem?
Do you know some guide more detailed?
I really would to learn it 
Thank you!