You may have noticed that there are two ways to initiate a sync from within Lightroom - Either by right-clicking on a User Collection in the Photosmith Publish Service, or by clicking the Publish button. Examples of both are shown below:
Which Way Should You Start a Sync in Lightroom?
The easiest method of starting a sync is in Photosmith, by tapping the Sync button while in Catalog Mode (discussed in Section 3.3.2) - however, if you would prefer to start a sync in Lightroom, your best choice is to always right-click and choose "Sync this collection with Photosmith." The Publish button will sync only photos known to Lightroom - this is just a function of how Lightroom's Publish Services work.
Imagine this scenario: You add photos to an already-synced collection in Photosmith, then press the Publish button in Lightroom - These newly added photos won't be brought into Lightroom from Photosmith. They will remain on the Photosmith side until you either right-click sync in Lightroom, or tap the "Sync Now" button in Photosmith.
We understand this is a bit confusing, but it's something that's out of our control right now. We don't have the ability to remove or disable the Publish button in Lightroom.
When in doubt, right-click sync in Lightroom, or tap the Sync Now Button in Photosmith.