Environment:

Dual monitor setup: 1920x1200 and secondary monitor 1024x768

Elemental main window on laptop monitor  Impulse running on secondary monitor

I clicked on Impulse to view content while Elemental was running on main monitor. Elemental minimized to toolbar and then threw a DX Error:Invalid call dialog and stopped running.

Debug.err & DX Diag zipped & loaded to Dropbox share at http://dl.dropbox.com/u/5732530/Elemental/DXInvalidCall.zip

Behavior appears similar to https://forums.elementalgame.com/387072 

Additionally I am seeing a line down the midpoint of the screen and a line across about 80% of the way down the screen when the bacground image is rendered behind the main menu until the world is built and the map actually loads. I tried to capture a short video of the intro but Camtasia didn't capture the game.