I’d import the sword and scabbard separately in the obj. format. For whatever reason, its not common practice to use the 3ds format if you intend to save to the prop library. Make sure everything is unchecked in the import dialogue. Both objects should arrive right where you placed them in the modeler. Parent the sword to the scabbard.  

Download my free stuff here: http://www.renderosity.com/homepage.php?page=2&userid=323368