My Hacked Rom crashes...will EXPLAIN

I only use three patches, the weapon axe patch(by PocoLoco), the FFIV Boss Battle Music Patch, and the FFIV Battle Music Patch(credit to metroidquest), and I change the sprites but my hacked rom crashes. I use a regular FFVI rom from coolrom.com and I am able to patch them roms successfully but my rom crashes after I enter about two random battles, for example in Narshe I get to the point of where the Narshe guard says "We got 'em trapped now!" I enter battle like normal and then the game crashes. Any explanation for this?