Step 1:

Go to the rear view of your rack and Unlock the document (press the 'Unlock/Lock' button in the Snap toolbar - it's the one with an open padlock on it). 

Step 2:

Drag a selection rectangle around the objects you want and then Copy (Ctrl+C).  Note: do not use Ctrl+A to select, as this will select everything in the document, whether it is visible or not. 

Step 3:

Return to the Front View and Paste (Ctrl+V).  The rear view will be pasted onto the Front High Detail Layer, down and across by one gridpoint - you can use the arrow keys to move it to an appropriate place.  Note that the rear view you have pasted will be broken down into its component elements since you have pasted parts of symbols, not symbols themselves.  Note also that the paste action can take quite a long time, depending on the complexity of your selection, as Stardraw is performing many transformations on what might be tens of thousands of objects.