I have a game breaking problem with my mechanic shop not producing any visible or usable mechanic parts at all. When I click on the shop it actually shows the parts being built eventually after gathering the scrap, and yet my parts total will stay at ZERO. I've had a partially built wind turbine for days now(18 of 20 parts)I just need 2 more parts!? But they never come. The parts never arrive by any carriers, even with prioritize option. Am I missing something here? Do any building require constant maintenance with these parts or is this a bug?