Hi!
We have had this issue in our office after we changed to AutoCAD LT 2016:
The program is freezing after you change from layout to model space. Sometimes it takes few seconds, sometimes it freezes completely. Also annotative scale text is working slowly and the cursor can start to lag.
We are using big xref which is turned from ArchiCAD to 2D format. Before the same xref has been working perfectly and not causing any issues. I have checked with our IT support all the computer issues and everything is seeming fine. Also I have reinstalled the program and tried to work from the desktop (all our files are in our server).
I myself have been working with 2016 for a bit longer than the rest of my coworkers. The problem started when the rest changed from 2012 to 2016 version. Also without the xref everything is working fine.
One additional question: I don't get this insertion scale thing. When ever inserting blocks the scale has to be 1 and when inserting xrefs the scale has to be 4. Is there any way that you don't have to change the scale in every situation? Before this was not hapening. Insunit 0 is not working.
Thanks for help!