I installed the DOSBox(version 0.74-2) in CM3 DevTerm, but it does not work well in fullscreen mode. I’have tried to modify ~/.dosbox/dosbox-0.74-2.conf, but it doesn’t work.
I modified these lines in ~/.dosbox/dosbox-0.74-2.conf
fullscreen=true fulldouble=true fullresolution=1280x480 windowresolution=1280x480 #output=surface output=opengl
But it is still not in the center:
Maybe you should play around with the width?