Hi all! I have the same problem running Pro Pinball Timeshock! game with DOSBox 0.74 and can't set 1600x1200 :'(
I can only set 800x600 as maximum resolution.
I try "machine=vesa_oldvbe" on the Dosbox.conf but still the same,
I try also, find another version of Dosbox (md-5?) as you say, but...