I have such a basic question, however I am puzzled. Can I copy a part of one song and then paste that part into a different song using MMM12? How is this done?
When you say "part" of a "song", what exactly do you mean? Do you mean just a segment of an entire arrangement (song) or just one object in the arrangement?
In either case you can export a single track or the entire arrangement (song) as a wav file and then import it into the new arrangement (song). Then, you can modify it as desired.