... but you are restricted to make a difference between the file extensions only, aren't you?

Why shouldn't it have a flag that you can set in the script to search for the external textures of the models and add them to the published folder?

http://www.puppenheim.org/
http://www.wuerfels-welt.de
Old Game Tutorial: http://www.puppenheim.org/MITutorial.zip
Free Game Editor: http://puppenheim.org/AlienalsWeihnachtsmann.zip
http://www.puppenheim.org/blender_starting_main_settings.txt