This recent thread illustrates setting a different card for each of the sub-components of a DirectScrollBar.
It sounds like you are confusing the “frame” with the “canvas”. A DirectScrolledFrame’s frame is the fixed part of the frame that doesn’t move when you move the scrollbars. The canvas is the part that does move. If you want to put a background texture on the canvas, create a DirectFrame of the appropriate size and attach it to the canvas.
If you don’t like the auto-placement of these buttons, you can place them yourself. The component names are horizontalScroll and verticalScroll. You can set parameters on these components in the DirectScrolledFrame constructor, for instance like horizontalScroll_manageButtons = False, horizontalScroll_incButton_pos = (0, 0, 1).
David