Layout Overlap scaled drawing on Sketchup Model crashes

I am not sure I am doing this correctly:
I would like to add to a view of a Sketchup Model in Layout.
I add a Scaled Drawing with the same scale over top and draw there.
Unfortunately it seems to freeze up Layout every few minutes.
I have to kill Layout from the Task Manager and restart, loosing work all the time.

Am I taking the wrong approach?
If I draw directly in Layout the scale is in paper units…

That’s not the same as crashing.

Hard to say. Share the LayOut file so we can see what you are working with.