Imported Curvy- game won't start

[Jake]

I just double-checked and imported Curvy from the AssetStore into a fresh 4.6 project => No problems! And obviously there is a Plane constructor with three arguments: http://docs.unity3d.com/ScriptReference/Plane-ctor.html

Could it be that you have other code in your project that defines a class "Plane"? If yes, that's a bad idea as Plane is a builtin Unity class. If not I would guess your 4.6 install is somehow broken...