I am looking for a way to locate duplicates in Lightroom CC and a way to lock edits on shared albums.

For duplicate detection, try out the Clean Up feature in Lightroom Web -- lightroom.adobe.com.  There is a “Duplicates” tab for identifying and acting on all duplicate and similar photos.  We’re doing an update soon so any feedback you have would be great.

For sharing, you fully control what you allow others to do with photos in a share.  Folks cannot delete photos you share and can’t edit them if you prevent that.  Take a look at the options there and let us know if anything is missing.

-Peter