If you take a look at the exported folder in the psd_template directory you should be able to see the structure of how a character is built.
If you just want to create a hair for the muscular guy for example, all you need to do is create a new folder in the assets directory, and call it char_mama_whateveryouwant. Create a pictures directory in it, and then put your image named 1.png in the hair (for preset colors) or col_hair (this is generally white items, can be colored in the program easily) directory.
If you’ve done that go the package_generator, and run the .exe with the following command line: ePicPackageGenerator.exe char_mama char_mama_whateveryouwant. Then all you need to do is let the program now that this package should be visible, open the packs.txt and enter char_mama_whateveryouwant in a new line.
You should be able to see you new pack in the generator under the ? icon, and if you run it you should be able to select your new hair.