I have written an interface that allows any user to see the block logs on their Empire and Kingdom lots. It shows all and any changes to lots done by other users (not by the lot owner).
So if you want to know what others did on your lot, please just go on this page and check it yourself! You can find it also under the “information” menu. If you suspect someone of griefing, please check there first, then talk to the person in question and ask them to un-do the damage. If that does not help, please submit a ticket.
This log does not (yet) show kills and chest access. That will at a come later stage.