Is there anyway to remove a path after adding it like so?

add_folder("%EXE_DIR%\\work\\Levels");
add_folder("%EXE_DIR%\\work\\Levels\\Dyna Greens");
add_folder("%EXE_DIR%\\work\\Levels\\Dyna Greens\\Lightmaps");
add_folder("%EXE_DIR%\\work\\Levels\\Dyna Greens\\Materials");

I need this since I have many levels, and would easily go over the path limit if there is no way to remove file paths. I basically want to manage what file paths I have according to which level I'm using.

Also, is there anyway to have a script exclusive to the level your loading? I like how you can do this when loading out of WED or SED(set thru map properties in WED), but I can't seem to find a way to do it in game(cannot add includes in functions and remove them). And level_load doesn't take the levels script into account.