Actually, you don't have to get the comic book to understand it.
For example, you understand a keyboard right? But you don't get how it works, you just know you press the keys, etc.
Oh, and in Countdown, they also have tentacle things inside, one of which stabs temporary General Worf through the chest. Don't worry, he lives, but ow.
My guess is the ones outside can move, it's just that they weren't compatible with Romulan systems and therefore couldn't operate.