Since I can't set the black canvas for black background, I have to use black square but I can't send the black square backwards. My template is finished but adding the black square now will make the whole template black. Can't send the square to back so I had to redo everything.

Update: Nuts, I just finished redoing all my templates and just now figured out you can send elements forward or backwards using the up and down arrows just above the list of elements on the left. That is not obvious, so maybe you could add there some label showing what are the labels for.