So i tried to use the events. I looked into the manual and typed that:

ball.emask |= (ENABLE_BLOCK|ENABLE_ENTITY);

Without ENABLE_BLOCK the script runs without problems, but with ENABLE_BLOCK (the same for EVENT_BLOCK) I get this error:
undeclared identifier. So, whats happened to this special event? All other events are running without problems...
MfG
Patrick