The Apoo system requires Python (>= 2.1).
Until version 1.4 Apoo interface required Tkinter.
From that version on it requires pygtk: GTK+ for Python, and also (gtk, pango, gobject).
It is mainly maintained for GNU Linux Systems.
It is available as package for Debian in its standard distribution. Packages and sources are available here. And if you really want an executable for Windows can be found here.