I'm thinking to try to edit the tilesets in this pack to make them compatible with rpgm MV... Or have you already tryied to do and the result appear orrible?

I haven't tried it but I do know that a lot of it would have to be redrawn as simply scaling up will not give great results. 48/32 = 1.5. You end up with some distorted pixels if you try to scale the tiles up from 32x32 to 48x48.