When opening the map in either the game or in the editor will often cause the game to hard freeze. A horizontal bar pattern will be visible on screen. A computer reset is required to get out of this state as ctrl+alt+del and alt+F4 are not responsive.
This issue was only found with my new AMD R9 280x (Asus DirectCU2 3GB) video card, the issue was not present with my old HD 4870 AMD chipset gfx card.
No logs are in Event Viewer or anywhere else. By the looks of it, the whole system hangs, including kernel, IO, networking. Sound loops the last-transmitted sample. {F22786}