Ensure you have the decrypted Ver 1.1 update file.
While the update originally fixed minor gameplay glitches, it is now primarily used to enable community-made optimizations: Monster Hunter 4 Ultimate- Update 1.1 -Decrypte...
Capcom originally deployed Update 1.1 to stabilize the Nintendo 3DS ecosystem, but it plays an even larger role in modern emulation environments: Ensure you have the decrypted Ver 1