Initially, I tried registering while logging a model from mlflow and got:

"Got an invalid source 'dbfs:/Volumes/compute_integration_tests/default/compute-external-table-tests-models/test_artifacts/1078d04b4d4b4537bdf7a4b5e94e9e7f/artifacts/model'. Only DBFS locations are currently supported."

WAT?

I got this when trying to log a model and supply a model name.  I can also reproduce by calling the REST API directly.

After some trial and error, I found that using the source: 

'dbfs:/dbfs/Volumes/compute_integration_tests/default/compute-external-table-tests-models/test_artifacts/1078d04b4d4b4537bdf7a4b5e94e9e7f/artifacts/model'

"worked".

But a new version never got created.

Also, the documentation doesn't mention the required run_id and source parameters.