The big problem with building the Child's Play window-builder was getting widgets in Smalltalk/V PM to move around the screen and dynamically resize without leaving "mouse tracks" or flickering. We struggled with this problem for days. Finally, CharleneBenson solved the problem by writing a method that did some fairly obscene things to the low-level Presentation Manager libraries. We found that changing even a parameter value or the order of the calls in the method would make it fail, thus the name "Charlene's Magic Method".