Creo Imaginem and Perdo Imaginem explictly state they can affect all 5 senses; the same seems to be true of Rego Imaginem, which just refers to "one sense" in the guidelines.
Illusory touch is described as the sensation of touch, but if someone pushes past the sensation their hand will go straight through the illusion.
Based on this, I'm puzzled as to why the Muto Imaginem at the highest guideline says "change the object completely, in all things except touch." (ArsM5, p. 145). Why this specific exception for Muto? If I make a box look like a bale of hay, why can't I make it so someone touching it will feel hay? Is this an intentional exception, or an unintentional one created by poor wording that needs errata?
I also note that none of the example Muto Imaginem spells create an illusion of a different size than the target. In fact, Image Phantom, page 146, seems to explicitly forbid it - "The illusion cannot be cast on things that have a shape or size improper to the final appearance". Does this mean the exclusion of touch in the guidelines is intentional, because Muto Imaginem can only ever change the surface appearance of an object but not its size or overall shape? But if it can't change the size, what Technique would be used to make a man look like a giant or a dragon? If it can, what are the guidelines for illusory size change using Muto Imaginem?