when i got it had (U) next to it, and no it hasn't happened to any other game. i've tried playin on both v1.4 and 1.6 of pj64, 1.4 works but the walls in the game are black making it annoying to play.....and 1.6 has issues loading native saves on megaman 64, more like unable to reach the load saved data menu. It works perfectly fine w/o any saved data. because i went into the load saved data menu w/o any problems before i started , because this happened before to me, thinking it was just the rom. but now it doesn't seem like it.