Thanks. Feel free to use what you want from mine, they're open source.
You could not do anything with the credits other than get three achievements. In my Day 9 devlog I explain about that. You can read my DevLogs here: Katamari Mech Spacey DevLogs
Can you give me more info on which item pickups were not volume adjustable? I spent half a day on that and I could have missed something.