...the figures seemed to have a raised insignia on their shirt uniforms, rather than the decals Mego figures had. A little customizing touch Robot Chicken did, I guess.
Not just that, but the chevrons had the division insignia as well. The Mego dolls just had tissue thin silver foil with no detail pasted upon vinyl plastic chevrons. Seth Green and his troop actually "screen accurately" enhanced them. (That's an odd phrase.) But since "day one" they have left the simple sleeve braids "as is", probably to keep some of that vinatge Mego feel.
Robot Chicken has done a few other "bits" set during the TOS, a short clip with the turbolift slamming shut on Kirk's family jewels, one I call "revenge of the Redshirt" and a fairly recent one when systems aboard ship fail, so the characters must perform their own sound effects and incidental music. Debatably the most inventive was a less than 2 minute retelling of "The Wrath of Khan" performed as a stage opera. Custom figures were sculpted for that one, including a Kirk with the appropriately aged faetures dressed in the burgundy jacket and a Khan in his Ceti Alpha V attire.
On a tangent note, Patrick Stewart himself performed the voice of a dune buggy driving Gurny Halleck in a spoof of "Dune" last week.