Editor changes to "inactive"

Hey there.
I grouped some meshes because i need a few copies of this arrangement. Everytime i copy that group (Alt+Drag) or (ctrl-V) my Editor (4.8.1) freezes and if i take a look into my taskmanager it says “inactive”. After about 2-3 mins the editor is working again, status “inactive” disappears and i can go on.
I am aware of the fact that the program needs to copy, build, render etc that into the scene, but i think its very long time for a bunch of meshes (9 pieces).
do i really have to wait 3 mins until i can go on? Is there a way to speed this up?

MS Windows 8 Pro (x64)
AMD FX - 6100 six core
AMD Radeon HD 7700 Series

thank you

What kind of meshes do you use? -> tri count + material complexity :slight_smile:

4 spheres, 4 cubes, its part of a rail for a staircase

just solved the problem by creating a static mesh out of the whole group.
I think the main problem was a reference to the other meshes by copy/pasting them into the level. now everything is fine and fast, thx for help