To use it is very simple -- see WindowMenu.h for all you need to know. The only difference in use between this and ScriptMenu is that you must call UpdateWindowMenu() whenever the windows, their titles, or their layer order might have changed. I simply call it before any menu access; it doesn't cause any noticeable delay.
Note that the code is in C, but I've used C++ style comments. If you're using CodeWarrior, that's not a problem; if it bugs you, let me know and I'll change it.
If you have any questions or comments about the code or its use, please write to me at firstname.lastname@example.org.