lsystem_build undefined error

when attempting to run lsystem on blender 2.41 or 2.42a i get an error message regarding lsystem_build not defined. if i copy and paste the lsystem_build definition into that error goes away but another appears. I believe i am having trouble with multi-file python scripts here. I have run lsystem on version 2.41 successfully many times before. I have since, installed Microsoft’s visual c# express edition and vaugely recall a message box saying that some python scripts may not work properly. is there any way to work this out without uninstalling visual c#?

i am running win xp sp2, blender 2.42a, python 2.42, and have set my PYTHONPATH environment variable. i have no problem with single file import scripts such as Treal import.

btw. the errors began with a cos undefined error, so i typed in the following

import math
from math import *

this tells me that my blender and python versions are communicating ok