I have two authentic Angelcakes I purchased from a counter back when High Tea came out; one is BNIB, if a little beat-up, and the other was depotted.
For the color itself, Angelcake has a very obvious cool pink sheen to it when swiped, but the shadow itself is a wamer coral-pink. My guess is that a fake probably won't get that quality right, because the light has to hit it at the right angle for you to spot it, and it's not very noticible in the pan.
Based on your photos alone, I think it might be a fake.
- The shadow got banged around enough for the MAC logo to scratch off the lid, but the box is in better shape than mine.
- The logo on the lid is obviously crooked (yikes!).
I took a lot of photos, so I've only posted a few, but the rest are on my Flickr if you click a photo. Wouldn't you know that the forums don't support the standard BBCode resizing spec?