Ok, is see now, any new fixture i put in is not responding !

so no problem with the specific Led spere or Octostrip !

I have to say, that I have this problem, after importing multiple Google sketchup models. (my file is now + 40 MB)

It was something very stupid.

I had created a new layer and the "simulation" option (in layers tab) was not checked.

then the new imported fixtures are visible but will not respond.

so, solved.