I have three 1920 x 1200 monitors and generally record at 720p (1280 x 720). When I start a Camtasia recording, it sets the recording area automatically to the last region I recorded, today that's top left of M3. If I want to switch the screen being recorded, I'll just drag the preview area to another location. I'm not sure exactly what you are asking for, a switch to automatically move the recording to x,y area to M1? Where would the switch be? And what would you select?