thanks again. the first solution you suggested doesnt work, because i need to use the shader - there is also a flashlight i have.
the other solution is tricky, because there is a complete dialogue-system with every character. i tried the following:
make characters invisible with only one invisible frame for "standing" and "talking". in this one frame i wanted to trigger animations, which were displayed on the smartphone-interface. it worked for one character, but when i changed to the next, no matter how i tried, the animation were not shown, although i did exactly the same.
i believe it is a too "dirty" solution. ;-)
but thank you anyway. i really appreciate your ideas and the exchange within the forum.