Repro
Open the Direct Offline Processing window - use the button in the upper toolbar. It will be lit with the window open.
Close the Direct Processing window with the same button - it is now un-lit and the window is closed.
Re-open the window - again using the toolbar button. This time the button is again correctly lit, but the processing window does not open.
Click the toolbar button again - this should un-light the button and close the non-existent window. What you get though is a hard crash. Repeatable for me 100%.