Looking for tutorial for door animation using mecanim

Hi -

I'm trying to find a specific kind of tutorial or documented example for building an animating door using Mecanim. It's clear you CAN build such a thing, but despite multiple Google attempts, I can't find a link that explains the process clearly. (I've seen threads that discuss such a system, without detailing every aspect of its creation.) And it's hard to find a Mecanim tutorial that isn't focused on character animation, which covers much more ground than I'm dealing with right now.

The system I need to build has these requirements:

• This is a 2D game, using animations hand-built in the Animation window. * has a door (actually a pair of double-doors that operate in sync, driven by a single animator) that can be in open or closed states.

• They need to start in either closed or open position. (My current attempt has them running either their "open" or "close" animation on game start.)

• I should be able to flip between open and closed state at any time, and (preferably) be able to switch from opening to closing in mid-animation.

Does anyone here know of a good introductory Mecanim tutorial, that builds a simple "open-closed" (or "opening-open-closing-closed") state machine, and explains every aspect of it? 2D would be preferable but I should be able to translate ideas back from 3D to 2D. Even a simple (non-character-based) Mecanim tutorial would be a great help.

Thanks for any leads you can provide.

UPDATE: I rewatched the Doors portion of the Stealth tutorial, which showed one approach (putting a single frame in each animation node, and letting the blend drive the movement between frames). This works for now, but doesn't handle two things I want to do:

• Have more complex door opening motion (such as moving through two keyframe poses during movement.

• Be interruptible in mid-animation (my current Mecanim setup does not do this).

Thanks -- Slapworth