Go to Immediate>Restore and in the dialog which follows, select "Restore an entire disk" (the top radio button). Then select the source backup set and Snapshot. At the destination window, select your target volume and, from the pop-up menu, choose any restore method other than "Retrieve just files."

In the files chosen Browser, double-click either the root of the source volume or an entire enclosing folder which contains empty folders. Empty folders will be highlighted but not marked. When you execute the restore, all the enclosed empty folders will be restored. No other combination of restore types or file selection will restore any empty folders.

Be very careful when restoring. If you choose "Restore entire" or "Replace corresponding files" in the restore method pop-up menu, Retrospect will replace and/or delete files on the destination volume.