Okay, makes sense.
Do you have suggestions on
*why the code runs with the original poster from the thread?
*how I can realize the "import “Common/ShaderLib/MultiSample.glsllib” ? as described here
what does get accepted is the line
import MultiSample;
in the GrayScale15.frag
Should I put the files into t he jm3-core JAR to make it run?