I try Away 4.1 with ASC2 in FlashDevelop. All work, but in output panel have many Warnings like:

Warning: Initializer value NaN is not valid for type ‘uint’. An initial value of 0 will be used instead.
      public function Vertex(x:Number = 0, y:Number = 0, z:Number = 0, index:uint = NaN
...
D:FLASH LABAwayaway3d-core-fp11_4_1_0_Alphaaway3d-core-fp11_4_1_0_Alphasrcaway3dcorepartitionNodeBase.as:88
Warning: Assignment within conditional.  Did you mean == instead of =?
  } while ((node = node._parent));)

It is normal for Away?

Try Action Script 3 Project.

)) this there is Action Script 3 Project. I say ASC 2(ActionScript Compiler 2.0)
http://www.bytearray.org/?p=4789

Update your dev branch. This has been fixed.
https://github.com/away3d/away3d-core-fp11/commit/22a0ae7869fa4aba3e8f0d9e03a42def1659515a

Thank you very much, JohnBrookes!