For the file format, it is a serialized object or in other words a binary file. You should not change those to prevent malfunctions (copying doesn't seem to hurt though).
Key assigments and macros are stored in an xml file (save/keys_charname.xml) and can be changed using suitable text editors.
Key assigments and macros are stored in an xml file (save/keys_charname.xml) and can be changed using suitable text editors.