During the process of creating my own Mephisto theme, I found it very difficult not to copy from the other existing themes. Yet, not all of them have the functions that I need. After digging into the code and spend hours to figure out what I can do with the liquid in mephisto with out much efficiency, I finally come across these 2 links on Slash7.
Hope these will help you a lot in creating a custom mephisto theme! ;-)