Short answers, pulled from the story.
Ralph McQuarrie sketched early concepts while Brian Muir sculpted the physical armor pieces at Elstree Studios. Tashy Baines vacuum-formed the final suits inside Shepperton Design Studios after machine issues arose.
A 2011 UK court ruling declared the costume industrial design protected only for fifteen years. This placed the armor design into the public domain across much of Europe shortly after that decision.
Temuera Morrison voiced clone troopers in Attack of the Clones and Revenge of the Sith as well as playing Commander Cody unmasked. Daniel Logan portrayed child clones while Bodie Taylor played young men resembling Morrison.
Plasma cartridges held enough gas for five hundred shots though standard cells lasted about one hundred rounds. Stormtroopers carried thermal detonators sniper rifles heavy repeating blasters and mortars alongside their primary weapon.
Snowtroopers appeared at Hoth insulated against cold weather with polarized goggles heated breather masks ice boots and battery packs lasting two weeks. These items enabled operations in extreme temperatures during the Battle of Hoth.