Connect seems to have a new bug. Could others try this and see if they can reproduce it. In Calendar view click on an Activity then hit Quick Edit (not View Details: "pencil": Quick Edit). In the Name field edit the name and hit Save. See if your Calorie calculation disappears.
Also for those using Safari. When in View Details and I edit (pencil: Quick or Full Edit) and make changes all changes will save EXCEPT the Name. I can't change the Name from detailed view. Is this a Safari problem?
EDIT: Write down you Calories first and then you can replace the info with a Full Edit.