You can import objects that are in a file using “Voyage Plan > Layers > Import Voyage Plan Document or GPX File”. We have video with more details on how to do that in Importing Navigation Object Information (iPad and iPhone Only) - #2.
Soon this won’t be necessary as Coastal Explorer on Windows will be able to use the same Cloud-Synchronized Layers as the iPad/iPhone app. See Coastal Explorer Version 4.0.21108 for a little more info in that feature.