The problem was finally double. The Attach Actor to Component was replaced by AttachToComponent BUT there is also a bug with the ForEachLoop function. As soon you try to link something to the variables in/ou of the function, program crashes. This is a known bug (UE-31740) and will be fixed by Epic this week with a hotfix: https://answers.unrealengine.com/que...o-project.html Hope it helps