So the hunger overflow function of this mod is actually doing the opposite of what it says it's supposed to do.
What the food heals:

Hunger level before eating:

What Apple Skins is thinking that I will get from eating the food:

Actual hunger gained from eating:

As you can see. The amount gained is significantly lower than it is showing in Apple Skins. Whether or not this is an error on Apple Skins end is unknown to me. All I know it that something isn't functioning properly here, and I believe it has to do with the hunger overflow setting in this mod.

On a side note. I would like to suggest that when raising the maximum hunger value for players, that their be some kind of indicator as to where they are at. If you set the hunger to double(40), there is no way to tell where you are sitting after you fill the initial 20 hunger haunches. Whether this be done in a style similar to Overloaded Armor Bars/Health Overlay, or if it is just done by adding a number off to the left or right of the hunger for saturation and hunger levels doesn't matter much. I just think that it should be there so that people can at least tell what hunger level they are currently resting at.

I have also noticed that even when the maximum hunger is doubled, it still prevents you from eating after you reach 20 hunger. Not sure if this is something that can be implemented, or if it would require to many changes and end up falling outside of the scope of this mod.