In the installation directory are the files that correspond to the created player profiles. They are named save0.dsg, save1.dsg, etc.
After copying it to another name or directory, open the desired dsg file with a hex editor.
To unlock all cheats on the single-player cheat menu, change the following hex locations from hex 00 to hex 01:
hex 192 through hex 1a1.
Note: Settings any of the cheats on when in the cheat menu will trigger a message that using the cheats will not allow you to progress to the next chapter in story mode or increase your character level at the end of a chapter.
To unlock all 12 Arcade levels, change the following hex locations from hex 00 to hex 01:
1a8, 1b0, 1b8, 1c0, 1c8, 1d0, 1d8, 1e0, 1e8, 1f0, 1f8, 200.