Yeah, that option should probably not be deselectable. The current v1 version of the apps API doesn't let developers replace/remove original shapes. Such functionality is coming soon in our v2 API, though.
Any status on the v2 API? I tried the app this evening and it still keeps the original.
used it today no change
@PhilJohnson, @MarkA.Bachman, @ShaneBell
I made some changes to make use of the “Keep Original” parameter, and it has been updated in Easel.