I see the error below when I try to import a corrupted XML file to Thingoworx.
"Error importing: error, Import Failed: An Entity Name Must Be Provided"
I'm not sure why you see the message "Import Failed" when editing the existing ThingShape in UI.
Do you not see any extra message when hovering the mouse over "To Do" button?
If there are more information in Application Log, it might be helpful to find out the cause.
This seems some strange error. It should actually not show as we are not importing anything.
Is this Thing Shape in use by any other entity? Try taking an export of all entities which are dependent on this Thing Shape; then delete those entities and then try to make the change in the Thing Shape.
Then reimport it back.
Also, you can try to restart your tomcat to avoid any caching issue.
I hope it helps.