I'm a beginner user about Tersus too. I found the way to use image element in "Tree Display and Management" Module:
I think we need to insert a path url to "<Path>" in "Image".
In this picture "images/item.gif" is physically located "Tersus Visual Programming Platform\plugins\tersus.appserver_220.127.116.11\DefaultWebapp\images\XXX". (the first folder is your tersus studio install root, 18.104.22.168 is your Tersus version maybe others)
And another way in "Examples" - "File Library" - "Generate files list":(when files are stored in database)
Sorry the "Examples" in my Tersus is my language, you may find it in your Tersus.
I don't know much about the file path in database and browser url code,
"File/?_path=File%20Library%2FDownload&Id=3" means the file field where row Id=3,
"%20" "%2F" are all url code means blank space,
"File%20Library" means the File Library folder in this Example project.
I've no idea how to make a image to be background. Maybe it's easier to use CSS like
Maybe David would told us regular using methods.
For best results, use the Firefox browser..