Creating a custom staff

[lilypond]

I would like to write a custom Djembe staff. I added core examples, as  
simple and as short as needed. The noStructured example gives what  
works, but without structure. I would like to change this example into  
voices, Djembe staff, in the  score. I did an attempt, see my  
structure example, but it does not work.

Can someone show my mistakes?

Thanks,

Bernard

DjembeStructure.ly
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DjembeNoStructure.ly
Description: Text Data