The Prague Post has recently posted an article which gives some more details of the set:
“A person walking into the old Letnany airplane hangar would never suspect that it holds a massive arctic icebreaker, an alien lair or a soon-to-be-destroyed whaling station. Yet in one room the Arctic Ocean gives way to a massive expeditionary ship. Developments next door are downright frightening: The queen’s chamber of an alien race is taking shape.
The icebreaker took 10 weeks to build in London at a cost of nearly £20,000 (960,000 Kc/$37,000), but the benefit is immediate, according to Windus. “With computer graphics, you need to spend a lot of time making it real. With a miniature, you shoot it and it’s there,” he said. Considering the short schedule and the need to work near director Paul W.S. Anderson, who’s directing the live action in Prague, building the miniature set in this city was the only choice.”