...
After which the compositemodel currenttime is increased and all child models and run against the new time.
If model3 in dependend is dependent of model2 (model3->input(t) == model2->output(t)) it can not run and should wait for model2 to deliver the data. This could be specified on the model ( by defining
that it should not fail when input data is missing)
for another run of model2 . Instead it should just report as ok but not
increase its timestep.