Good afternoon...

I'm creating multiple sheet set templates for multiple clients with unique title sheets. The latest one I have almost finished, but here's the thing. The sheet set intermittently greys out and a lock appears next to the sheet set name. All functionality except plotting is gone. Same thing for sheets within the set. I close the set and reopen it and it's back to normal - but after I fiddle with one of the sheets in the set, it greys out again. I've restarted my rig, deleted and recreated the SS completely, and reimported the drawing, but nothing has worked. Can anyone shed any light on this?

Thanks, Tom