Hi Alessandro,
I figured out that you were not able to organise the symbols according to their state.
By default,all the symbols are organized according to their states ,but if you want to re-arrange some symbols under certain states,you can do it using the Model Explorer.
For proper understanding, here I am considering another example in Stateflow.
1.You can open this example by typing the below command in the command window:
openExample('stateflow/ModelingACdPlayerradioUsingStateTransitionTableExample')
2.Open the "CdPlayerModeManager" chart which also opens up the Symbol Manager. Go to the Tools section and open Model Explorer.
3.Select “RadioReq”,right click on it and cut the symbol.
4.Go to “Eject” and paste the symbol.
5.If you go back again to the Symbol manager,you can see “RadioReq” is listed under Eject.
I hope this resolves the issue.