FYI, the only reason the samples always unregister is because in the case of the sample, they are showing a workflow where some data is taken offline once, and that is it. Otherwise, we would end up with tons of extra replicas registered on the sample server.
As for the System.userHomePath vs ~ issues. The issue is that any ArcGIS Runtime QML type will require it to be a file URL, like this- "file:///Users/username/ArcGIS/Runtime/Data/Local.geodatabase". Since the local types require "file:///" to precede the path, we made System.userHomePath return the path with that prefix. However, FileInfo (from the Extras plugin) does not work in the same way.
