I wanted to post a solution I found for non-java projects needing resolve transitive dependencies for arbitrary artifacts. I am guessing that this would work for native dependencies, although I do not know how to refer to the dependencies in the new software model.
In any case, I managed to make arbitrary dependency resolution and retrieval work with Ivy (no Ant), and then purely in Gradle, using IvyArtifact. I uploaded the Ivy solution, and the Gradle solution.