These things have so many settings that counter each other it gets confusing real quick. Sorry if I repeat stuff you already have set.
First off, when you are inserting SBF fills, they can have either of two color values. In the SBF setting dialog box, you can create it with the Entity setting checked. When this is checked, your SBF will be: drawn on screen, printed, and Datacad's properties (when you identify it) set using your active color let's say Cyan. If this option is unchecked, you can click on the color box that appears to the right and choose an additional color, for this lets say it's a custom red color. Now when you draw your SBF it will be: drawn on you screen in red, but it's Datacad properties will be cyan. Also now when you print it there is an additional option in the pen table, to "Map Fills to pen colors". If we leave this unchecked, it will print our SBF based the RGB value of the custom red color we picked, just like printing clip art from Word for example. If it's checked, it will print using the Pen Assignments setup for cyan, including the pen weight & density (opacity). If color Cyan is set to Pen 1 and Pen 1 has the Map To Color set to a Color it will print using that color. Usually we will have this set to Black and then we can adjust the Width to get the printed output to print a specific width and if we want a halftone (grey) we can adjust the Percent Density down from 100%. If the Map To Color is set to a color other that black, it will print out in that color with the width and density set in the Pen Settings. If Map To Color is unchecked, the output will match the color of the display with the corresponding widths.
O.K. confused yet? That determines how the colors are selected for display and printing, now we come to how things get ordered. A Datacad entity's printing order is decided by the order of our pen table, printing all colors mapped to pen 1 first then pen 2 and so on. So if cyan is mapped to pen 1, and yellow is mapped to pen 2, then yellow will always print on top of cyan. Most of us know this because we use it every day. So whatever active color we draw our SBF's in regardless it it is using the entity check box in the SBF dialog box, they will print using this pen table hierarchy.
Unless.... in the pen table there is an additional setting under "Bitmap & Fills", where you can override this hierarchy, and force SBF to Print First (behind or below everything), Print Last (in front or on top of everything), or In order (use the Pen Table hierarchy).
We've got to be confused by now. Now if your SBF are drawn using the same color and are on the same layer you can use the Move to Front, Back, Behind, In Front options to re-order them additionally on a per layer basis. I don't recall if this will work across different layers.
I'm sure I have a few things a little off, but this should be a good start to understanding how things work. Hope this helps. This is where a updated manual would be a
big help