Failing all that, you can at least get around the 50Hz issue by using WHD Load and the NTSC tool type.
Considering how few games that actually were produced for being run under NTSC (although many just use the 320*200 part of the 320*256 PAL screen most still seems to have been made for PAL) there will be many issues involved in promoting them into NTSC.
It's not until recently I've decided not to bother about promoting games into NTSC to get full screen... just because most seem to behave odd. The scrolling often gets jerky, the music is, if not only running faster, get messed up, and some games even become completely unplayable.
I blame the lazy coders. It's shown again and again and again. How many times does not the intro pictures make use of the full PAL 320*256 resolution, while the game in itself only makes use of the upper 320*200 part of the screen (in other words, if the NTSC tooltype is set in such cases, intro graphics will be cut of cut of... like with PAL Lemmings)? This bothers me so much. Extremely unproffesional it seems. Not to mention hardware scrolling, how often is it applied? Not too often, I'd say. Oh, let's give the player jerky scrolling! The player doesn't care and it saves us some time instead of using the hardware scrolling! YAY!
Oh dear. Getting of topic, slightly, but, well, my point is that many many many many AMiGA games which had potential of being really nice, and actually in theory were, became bland just because of lazy, or maybe even uncunning, programmers. The games were just too often not presented in a good way although they often had good ides to be presented.
I am still to see one single Bitmap Brothers game run smooth. I hate them for not making The Chaos Engine a PERFECT game by just adding smooth scrolling. AAAAARGH!
