How many Featured Products Can Be Displayed

Running Zen Cart v1.3.9d. The site has been up for several years without updates since initial install when 1.3.9d was released.

This question concerns:

<CATEGORY>, <FEATURED PRODUCTS>

If one item is added to Featured Products it does not display as designed. So, we add a dummy product and turn it off. If five items are added to Featured Products only four products rotate on the Main page, displaying items 2,3, 4 and 5. The first item is not displayed. If eight Items are added to Featured Products only item 2, 3, 4 & 5 are displayed and rotate position, item 1 and items 6 thru 8 are not displayed.

The owner wants to add more products to the Featured Category, say 8, and have 3 or 5 them rotate. No matter what the max number is set to the max displayed seems to be limited to the 2, 3, 4 & 5th item position. If max is set to 5 then four rotate, ie set to 4 and 3 rotate.

If we try to display 8 items it will not do more than 5.
The <Configuration, Layout Settings> is set to 10.
The <Configuration, Maximum Display of Featured Products> is set to 10.

Any ideas where to look would be appreciated.