The internal framework is still heavily under construction, with additional lateral bracing now installed between the main radial beams. Additional lugs and brackets will soon be welded into place to allow for the installation of critical hardware, the first of which will be externally charged batteries and the field generators for the structural integrity field. The various hull segments containing holes for windows and other features are now in place, but the transparent aluminium windows themselves will not be added until the internal rooms are under construction. Here's a quick test of the iridescent hull plating, which is proving to be quite difficult to get looking right. You can also see the exposed framework for D Deck, which will contain three rings of crew quarters and a central computer/power distribution room.