When a popup message (in my case, a text message popup from Handcent) displays over SCUMMVM, the screen freezes. Sound continues, however. I suspect this is basically the same as Artifact 3178197, but with a slightly different trigger that was not anticipated (losing focus without losing the screen).
I first experienced this with version 1.5, current in the Market. I just tested with the latest nightly, and the same glitch occurs.
I am using a MyTouch 4G Slide, aka HTC Doubleshot.
My phone is rooted, and I am running MikTouch 0.7, which is a cleaned-up version of the stock Gingerbread ROM.
I have experienced this mostly with Woodruff and the Schnibble, as that is the game I have played most. I do not recall if I have gotten texts while other games were up.