you achieve this by running in 'full screen' mode

I'm having something of a similar issue, and I tried this fix, but it didn't seem to work. Specifically, it happens with Starcraft. Starcraft is locked at 640x480, and typically, it will be magnified and stretched to fit the full screen, when run in Windows normally, or in Boot Camp. In Fusion, however, it runs at 640x480 in a small box. Before I changed that line, when I tried to get a bigger window or full screen it, it would have the black area around it. After I added that line, full screen would instead revert me to a weird state, where there was a black box in the top left corner (I assume that's starcraft) with the rest of my normal desktop across the rest of the screen. Is there any fix for this?

I just tried adding pref.autoFitfullScreen = "fitHostToGuest" in Fusion 2.0 beta 1 and it didnt seem to have any effect. Is there a new way to do this for 2.0? Starcraft in a tiny window is no fun

Thanks.