How To: Insert an image with a caption
- Insert image on a new line
 -  Select image (by clicking on it) and use the right arrow key to move to 
the right of the image
 - Apply desired style to the paragraph from panel on right by clicking on 
the style name
 - Press Shift-Enter to create a new line
 - Type in your caption
 
You can put captions above the image by using the left arrow key, typing 
caption and then pressing Shift-Enter.
The principle is that you have a paragraph that contains an image. The 
style gets applied to the paragraph.
You need to use Shift-Enter because that inserts a soft-break just like in 
Word. This is so that the caption ends up within the same para as the image so 
there is no gap in the background colour.