Thanks for the responses guys... I can set it to windowed using the video settings ingame. I can move the (game) window around after bringing up the (game) console, using the mouse. I can move the window to the primary monitor. Setting fullscreen ingame still launches in secondary monitor. I do not understand or know how to: "set in to fullscreen in your WM". I do not completely agree on your standpoint that it has nothing to do with TDM. I could very well be the case that it is not TDM's fault but (Valve's) source games like portal for instance lauch fullscreen in primary monitor without any problems at all available resolutions...