How do I keep docked panes from moving around?

[jeff_rivers]

I work with these four panes docked along the right side of my workspace, and set to auto-hide: Layer Properties, Properties, Tool Palettes, and Xrefs.

In different drawings they move around.  That is, I prefer that Layer Properties always be on top, Object Properties be below it, Palettes below that, and Xrefs at the bottom.  See attached picture (which shows that Layer Properties has slipped down below Object Properties).  

What setting controls the order of these panes?  How do I fix them in place so that they remember their position between drawings?

  

[tcorey · Accepted solution]

Set LockUI to 1.