Unity 4.3 - Sprite opacity animation not working

[ArtCoder]

Hi there. I'm working with 2D Toolkit on Unity 4.3 trying to animate a sprite's opacity. I added a Tk 2d Sprite.Color curve to my animation and changed the alpha value in a couple of keyframes. When I play the animation, I can see the alpha value change in the animation window, but the actual sprite opacity doesn't change. Is this a 2D Toolkit limitation or am I missing something?

[unikronsoftware]

This is a limitation of the animation editor. It can't animate c# properties, only built in unity properties. We have posted an example adapter  in the forum, but it is usually much more efficient to animate using a tween package.