Both points relevant to some stuff I said in
Thread: Ultima Weapon a little bit ago; it seems to me that much of Ultima Weapon was in disrepair, but Nero got it up and running again with a little help from Gaius' shady alliance with the Ascians. Praetorium shows that they have a pretty good supply of back-up parts with those legs busting out of the walls everywhere, and the outer shielding of the restored Ultima Weapon is reminiscent of The Black Wolf's personal armor. I do agree that Lahabrea provided the heart - and that it
may not have been the first time he lent out some technology without fully explaining its purpose.