I cannot say you nothing for the Python code, and sorry if i write in english, but i don't know german.
But i can say you a thing. I have solved my problem with SDL states, and now my age is ready. There is an important thing i have understand....
I don't know if this can help you, but is possible have importance for your project.
For use the Boolean status into the Python Responder, you need write two responders for all objects, because if you use a responder multi states, it not work in correct mode.
Is true....i have test this in MAX, and not in Blender, but if you see your animations working but not save the state in the SDL file, is possible it is for that. All objects need a Responder for to open the door and a Resonder for to close the door.
After that you need link the two responders to the Python Bool Respond and added the voice writed into your SDL file.
If tihs not help you, i ask excuse, but hope can it. Good Job and Good Luck for your project.
By Jhon J. Jaguar.