After some digging around, I was able to resolve the issue. For those who may be encountering the same issue, this is what solved it for me:
For the issue with matplotlib: I simply needed to explicitly specify to cxFreeze to include matplotlib.backends.backend_tkagg. My setup file ended up looking like this:
import sys
from cx_Freeze import setup, Executable
packages = ['matplotlib.backends.backend_tkagg']
setup(
name = "myname",
version = "1.0",
description = "some description",
options = {'build_exe': {'packages':packages}},
executables = [Executable("test.py", base = None)]
)
As for the BeautifulSoup issue: There are a couple of posts around the web that have dealt with this issue: cx_freeze sre_constants.error nothing to repeat, https://bitbucket.org/anthony_tuininga/cx_freeze/issue/59/sre_constantserror-nothing-to-repeat. The relevant conclusion: something is wrong with the 4.3.2 build of cxFreeze that causes this issue. I simply used cxFreeze 4.3.1 to build my app and the problem was solved. It may also be possible to rebuild 4.3.2 locally and have the issue be resolved, but I did not attempt this solution.