When working on a scene you exported from WebCC in Harmony, it is possible to download changes made to the scene by other users directly from WebCC into Harmony. Likewise, once you are done working on a scene, you can upload your changes directly from Harmony to the WebCC server. In both cases, this is referred to as a "partial update".
To perform partial updates, you must first add the address to the WebCC server in your Harmony preferences. Then, when downloading or uploading changes to a scene, you will be prompted to enter your WebCC username and password.