how to solve certain problems with the ICM (an algorithm)

[Vanquish]

Not only does this thread deserve to be bumped, but I have a question as well. What is the calculation used to determine the % stake in the prize pool (aka the ICM calculation)? I've searched and the best answer I could come up with is some Mathematica code that I, as NOT a programmer, do not understand. I was hoping to plug it into Excel and make a spreadsheet of various situations so I can start using this concept more in the live games I play. Thanks!