In the base texture pack folder where you run the script it should create the ~ConvertedTextures folder. For example I converted the star wars pack.
I really should do a proper writeup for using it to generate DDS packs because I know it can be cumbersome to learn. The whole generating DDS stuff was just a bonus, it's original idea was to just find texture issues. Anyway if you are still having issues or have any other questions or what not, we should continue the discussion here.
Spoiler: