Well the problem is that WordPress 4.4 change a few things and here are the changelog on how to proceed with the update....
4.1.10
WARNING! - PLEASE MAKE A DATABASE BACKUP BEFORE UPDATING
Auto execute script that will attempt to fix the widgets with wrong IDs in WP 4.4. Some widgets with bad data inside of them might need to be placed again.
Fix for wrong Widget IDs when placing them in WP 4.4
Encode the serialized cache data with base64 to avoid errors when unserializing in WP 4.4
Steve this could happen when updating to 4.1.10, we suggest you do the following: make a backup of the site and copy it to a different location do the update on it and then manually add widgets to it that is the only way i hope.
Martin do the same thing and when you are done i can take a look why isn't the overrides saving ...
Wow - that's a frightening solution... rebuild ALL the widgets - so basically, rebuild the whole site.... I don't have time to do that - I'm going to have to just not update.
It's not simply a case of getting the widget and re-adding it to the site. I cannot see the widgets anywhere... or is there somewhere I should be looking? Are they hiding somewhere just waiting for me to tell them where to go?
That would be great... but in my back end all I see are the widget separators - no widgets.
The thing that is most annoying is that this is a relatively new site and the first Gantry update breaks it...