The program was designed in the most straight forward way possible...for the sole purpose of users being able to pick it up and use it without needing a tutorial...
But if you do need help, there is full documentation under the help menu (Or in the default FPSC Toolbox folder). If that doesn't answer your question, feel free to shoot me an email, I'll be happy to answer any questions you may have.
AS for the character, there is an import option...You can import any character you want and just load a different texture, then re-export it. Its really simple.