Working with ADF Storage Event Trigger Over SFTP

The screenshots you've shown indicate a GUI to modify the event filters; I find this GUI in my Event Grid System Topic subscriptions, but ADF is not registering a subscriber when creating the file triggers, and so there's nothing to modify.  These instructions are unclear; what is being done to ensure the ADF storage event triggers are registering within the Event Grid System Topics? 

Update:  We learned that when crossing subscriptions, you must give the ADF Managed Identity the Storage Account Permissions, but you must also give the Azure Data Factory Application, which seems to be only one-per-subscription (even when multiple Data Factories) the correct EventGrid Contributor permissions for the ADF Trigger to successfully register the listener on the System Topic of the Storage Account hosting your SFTP front end.  Once this permission was granted to our ADF Application, publishing our triggers resulted in the correct registration of System Topic Listener, where we could then go and add the SFTPCommit event.