VC Runtime error when running Pythoncard app as an exe

When I run my Pythoncard app after building a py2exe app with this command line

python setup.py py2exe -b1 -c

My app crashes on startup, but does not make a .log file.
The dialog displays Microsoft Visual C++ Runtime Library "Runtime Error!"
"The application requested that the Runtime terminate it in an unusual way"

When I change the build line to
python setup.py py2exe -c

My app launches just fine, but then there is a directory full of many
dlls and pyds.

setup.py looks like this

from distutils.core import setup
import py2exe

setup(windows=['WxGui.py'], zipfile=None)

Does anyone here have experience with py2exe/pythoncard runtime problems?

thanks