Well, I installed the terrain toolkit, and I'm getting this message:
asked Sep 17 '11 at 10:23 PM
That error means that TerrainToolkit has not been upgraded to use current Unity API. Since it is just a warning, it should not cause problems. However, since it indicates that the author has not tried it with the latest version of Unity, there may be other incompatibilities that are problems.
All you could do is ask author to upgrade (or do it yourself).
answered Sep 17 '11 at 10:31 PM