Associate your classes with artifacts, and then you would be able to generate code.
Check in "Class Dialog".
Frage
It might be obvious (at least not for me), but I am incapable of generating my C++ code from UML with Bouml 4.23. So far i used the menu item "generate C++" and it always reports that it is "done" but it seems that I can't locate the files, or there are no files as the report doesn't state anything else than being done.
Lösung
Associate your classes with artifacts, and then you would be able to generate code.
Check in "Class Dialog".