There is a user command and an admin command called "limits". Admins can check the limits of a specific island owner. Both show a GUI panel with the limits and the current count.
This section lists the maximum number of blocks allowed for each block material. Do not use non-block materials because they will not work. The limits apply to all game worlds.
### worlds
This section lists block limits for specific worlds. You must name the world specifically, e.g. AcidIsland_world and then list the materials and the limit.