ops, sorry. I should have mentioned I used Isadora Core, which is able to read QC compositions if they have their inputs and outputs published.
Anyway, it is very straight forward: I made a compostion with only the syphon server in QC, then I published its inputs. Following I named the server name as “Scene” and the Application as “Quartz Composer”in the macro inspector. The same procedure with syphon client.
Then I saved then (server.qtz ; client.qtz) at the freeframe folder (it’s a predefined path for isadora to read) at the applications Support). Within IsadoraCore they are visible as “actors” : qc server and qc client. When placed in a patch, the actors can have their inputs edited.
Well, I could post a example somewhere if its the case.