For pictures, I put the image into the Texture folder and apply it as a decal.
Importing a jpeg works for the OpenGL image but if you then render it, it disappears.
Yep, you can't render an image.
In order to get it to show in the rendered image I right clicked on the Render Library window and selected “Create from image file…”. I then selected my jpeg on the desktop and added it to a materials category.
There is a Materials and Textures folder. The Materials folder has renders for solid objects, liken it to a block of wood, there is a top grain, side grain, and end grain. Your table has a top grain but the right end has an end grain that extends down below the table including the board below the tabletop. The selected grain can be controlled by using TextureSpace to select the plane or "auto plane" for the program to select.
Textures are like a surface. When a texture is applied it will tile, that is, repeat itself, think wallpaper or floor tile.
for a picture I use a decal. Put up a frame and place a decal in it, any decal. What you want is the decal palette where you can change the decal to your picture image and size it to fit.
The two screen shots show a fire in a fireplace and a moose picture on a wall using the decal method.