Before you fight the death meteor at sandstorm there will be a cutscene after you talk to everyone. When Dr Tros's name appears the first time keep a sharp eye on the name as the second time it appears it will be Dr Totos instead of Dr Tros.
When you have beat the game go to the Imperial town and go to the store. When you get in go to the man and view the items for sale there sould be dummy organoid and Zos prototype buy them and equip them to a zoid. Hope I helped.