Did you install wxPython in a separate location or in the Poser runtime? Ideally, a separate wxPython installation in a different location should not affect Poser's Python. Poser comes with everything it needs, so unless you develop with wxPython yourself have other software that requires wxPython, there is no need for installing it in addition.

The one thing I could imagine is that the separate Python installation set certain environment variables that cause Poser's Python to search in the other location.