Just curious for the “dateless inputs” as per my 2 screenshots.
Othervise it all seems to function perfect… is there a hidden wastebasket I need to empty? 
GreyT
I believe I see what you do.
In the timeline view, only items with dates are displayed in the timeline.
To warn you there are things that don’t fit anywhere in the timeline (because they have no times), Aeon adds an indicator. In your case, the timeline view is warning there are 1349 items that aren’t associated with any point or duration in time.
It looks like you have a setting for a certain item type where it can be displayed in Timeline View, but not in the Chronological order (Spreadsheet View).
You may need to add them back into the Chronological order so you can see the events again in Spreadsheet view (and delete them if you wish to). You can do this via Advanced Settings (cog icon, Data types tab, Edit). Click an item on the list of item types on the left and see if “Chronological order” and “Timeline View” are ticked under the “Show In” panel on the right.
You can also send your timeline file through to support@timeline.app if you wish us to look into what is missing.