Hello Ruben! Sorry for the delay on this…
This is a known issue, or more accurately a known feature. In order to assign multiple ConDoc tags, we had to take over the Hide command in SketchUp. So in ConDoc 5 you are not able to hide entities and save/update those to a scene. You have to work with tags.
Sorry for the bad news! I hope the convenience of multiple tags on one object overshadows the inconvenience of not being able to hide one off entities.
Let me know if that clears things up. Thanks!
Mike