The unlimited item usage and experience multiplier cheats do not work properly. EXPMod does not work at all, no matter how I twist the little arrow thingy after using it. Item usage seems to work with equipment and in-battle items, but not with food ingredients or u-material. There are no instructions for either of these options in the trainer.
The attached save file puts you in Ymir just after the prologue, where you can experiment with those options at will.
There is no file attached.
Okay, I've zipped it.
I'll give 0x90 a heads up.