Xport released a new version of MednafenX-NES(info).
What's new/fixed:
*(v3) Yet another possible fix for garbled video on 1.6 xbox's
*(v3) Games with battery backup RAM (e.g. Zelda) would save the first time you exit the game, but then would fail upon subsequent saves until the emulator was restarted. Fixed.
*(v3) When using the USB mouse or joystick to control the light gun, pressing one button will fire normally and pressing the other button will automatically fire off-screen (cursor automatically positioned to upper left corner)
*(v4) Yet another possible fix for garbled video on 1.6 xbox's