I made a dump of my original Ys 4 CD with CDRWIN it plays great with Daemon Tools and Magic Engine on the PC. So I Uploaded it to the XBOX and it won't boot if I select to use the Orginal CUE sheets... same thing happens with my other 12 Original TG-16 CD games..... I also notice that while playing Ys 4 that some times the CD music will stop playing when you go from screen to screen or bring up the menu screen to see equip, magic, item, etc and go back to the game. The only way to get the music back is to go into the emulators in-game menu and go back out.
Also I was thinking of an improvement to the way you do the aspect mode setup. The current problem is that not every game uses the same resolution. An example, Bomberman has a resolution of 256x224. Now if you load Dragon Slayer it uses two different resolutions, 256x224 and 336x256. So what happens is the game will look stretched with the current way you handle the screen setup. The same thing happens if you config the GBA emulator screen to GBA Mode aspect then got play a GB or GBC game, the GB and GBC games look stretched. I was thinking as a way to improve this, that you could go into the Main Config and set the Screen Resolution for your TV. Then when you go to load a game it will detect the current resolution the game is using and automaticly scale the image up to the max screen size you had set in the main config while keeping the aspect mode. This way we don't always have to set the screen resolution for each game anymore.