A couple more questions for you:
I have the feeds set up to run every day, though they don't seem to be bringing in new stuff. What's the mechanism you use to kick off the daily feed, and is there a place to set a preferred time?
My setup may be a bit atypical. I've set up one Events Manager/ESS instance to serve as a central hub for a number of related site's calendars. The idea is that each of the 'spokes' can act as feeds to the central hub AND can download the feed from the hub. The individual webmasters can then decide which events to include on their site and which not.
When I do a manual run I seem to get a lot of duplication. I see that each item in the XML has an EventID stamp and the EventID coming from the source server is the same as the EventID on the same event coming from the central hub server. It seems that it would be relatively straightforward to check against the list of previously downloaded EventIDs (or ESSID in combination with EventID) to avoid duplication.
Is there a way to see the EventIDs in WordPress Admin? Then maybe I could figure out why I'm seeing duplicates.