It seems to me that the problem might be specific to the Classic-Craft Mahogany door in the Therma-Tru Exterior Doors category.
You should login to the admin area and uncheck the box that makes this particular product live then test this again. If you can see the remaining four items and not this one then there is a problem with this item.
If you can determine that the problem is with this item we can then look into the values for this item to see what the problem might be. Please post back and let us know the results.