I have an extensive library of movies and TV show with many episodes. I have created views for Unseen Movies and Unseen TV shows that propagate based on Last Played is "never played". This works well, but the tag is not editable, so other than playing it and skipping to the end, I don't see a way to enter a current date/time stamp. I'm looking for a way to tag a field for video as "seen". I've tried Library Tools > Mark as played which does modify something, but not sure what. It doesn't update Last Played, which kind of makes sense that it should based on the tool title. It would be great if this tool updated the Last Played tag with the timestamp at time of use. Otherwise, what is it changing so I can use that field in the rules for my unseen views? I haven't been able to easily find it.
EDIT: I found that it toggles "Number Plays" from 0 to 1. I used global change to modify these unseen files using the tool to <empty> and updated my views to use this modifiable tag instead. Problem solved, except that this Library tool doesn't update the Last Played tag, but that's OK I guess. It would be nice if it also updated that field to timestamp when selected or never played. A future change would be nice.