I use usb loader gx for a few weeks now, and at first it worked fine. i had 2 games on my usb, nsmb and muramasa. The showed up and i could play them perfectly. Then i put modern warfare relfex on it but it didn't show up in gx. However, i am able to play it on neogamma. the same goes for resident evil darkside chronicles and F1 2009. I have the latest version.