FWIW, I've documented the steps I took on the qtocc-wiki
http://qtocc.wiki.sourceforge.net/opencascade_osx
The full set of dynamic libraries to run the application were about 120 MB. The fully compiled OCC folder is about 2.5 GB. I only have a Powerbook (PPC) so these were not universal binaries.
And beware that the visual OpenGL-based views only work using X11.
I was not able to compile the qtocc on Qt4 since Qt4 for Fink did not work for me.
Maybe this will help you out a bit. I would appreciate any updates or corrections too ;)