Although data changing can be used to edit LF2 in many different ways, it does have its limits. There are many aspects of LF2 that cannot be modified with a data changer. In order to change the background color of the title screen or increase the number of stages in stage mode, you need to edit the lf2.exe file.

Generally, EXE Editing is only useful if you're making a complete mod or version. It allows you to give your modification a unique feel and new features. Editing the EXE file is considered by many to be much more difficult than data changing, but if you put some effort into it, it'll really increase the overall quality of your work.