Haven't used cfg usb loader but using usb_loader you can specify certain settings for various games, most of mine worked with the standard settings it came with but there were a few that needed different boot things? sorry can't remember what they are called it's been an age since I used mine, like 202 or 249 etc, will have a quick google to put the right info in here, sorry for the vagueness but it might help
Just the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.