I decided to design a custom application support folder icon, and since it might be of use to others, am posting it here. (not sure if here or the developers' forum would be the best place).
Best results need a sharp image that looks good in 1-bit. For Hangman, I choose to use a noose that had been part of the original icon and thresholded it until I could see the rope detail without making it too noisy:
The template file is here: http://mateo.elahorcado.net/blogimag...onTemplate.zip
Edit: For reference I've included my application icon with the folder icon made from it.