I deleted a Sliding Door Slide and Page from the Sliding and Primary Navigation menus. I replaced it with a new page and updated my media with the intended sliding door picture. It is the 4th slide. The slide is white / blank. The picture I want to insert doesn't show. For my other 6 slides, In the past, I selected "use as featured image". This option is not longer visible.
Back in 2012 I decided to use Sliding Doors. It is not a user friendly theme unless you are familiar with code (CSS). I am not and therefore, have depended on the steps offered by other users in the FAQ of the author's site. To find any useful information, I have to spend hours sifting through FAQ's that are not pertinent to my issues. The author, Wayne, has not made any notable contribution to support current issues; but he does chime in from time to time providing a link back to the FAQ's on his support site. These links point to outdated answers and are of no use with the current version of Sliding Doors. Case in point: A pictorial on how to add a picture to the sliding navigation menu stating to select it as a featured image...which I can no longer find. There are no comments on updates or changes made in this area.
If I get a response to my above question in the next 24 hours, I will update my review and increase my rating.