While it's true that Karra's encumbered right now, her natural speed is 8 squares, so although she's encumbered she's not slowing the party down at all; she's actually at the same speed as the party (6 squares).
Just thought I'd mention that... just in case that was a part of the reasoning
Also, what sort of device is the hangar door security panel? If it's more like a security card device, then it's a matter of hot-wiring or otherwise bypassing it, which falls under the mechanical side. But, if it's more of a keycode-type device, specifically with its own mini-computer, then it might fall under computer use instead... it doesn't seem that clear right now which it would be.
Then again, thinking about it further... Karra doesn't have a PDA or a laptop that's designed to interface with and hack the panel (since I'm imagining it to only be a keypad on the side of the door), which means it'd have to be physically hacked anyway...
So, I guess the question is supposed to be... is this something for Computer Use or Mechanics? Some of the dialogue in my post will probably vary, depending on which it is...