I just did the autoupdate and now my mesh editor won't open. I get a small error window that simply says "Error" in the window heading bar and the message says, "Can't load pak "../data/engine.pak" and has a button that says "ok"

Mesh Editor.exe was removed (you can autoupdate with selected "remove additional files") it will remove the useless .exe and other files

Mesh Editor is now available in the new tool "Editor" (please check version history)

Aah, ok, got it working now. Thanks.