Bukkit

What steps will reproduce the problem?
1. Set default flag use deny at the config or set it manually ingame after setting a ProtectionStone.
2. Try to open a chest or use a button (in your own region of course)
3. See an error message

I think the problem is associated with the missing UUID support so WorldGuard prevents all use interacts for this "unknown" player.
This only affects if you globally allow "use" at the WG configuration and try to especially deny it in player regions.

git-Spigot-47b1dff-f233e7d
ProtectionStones v1.9i (ProtectionStones-1.0-SNAPSHOT build #5)
WorldGuard v6.0.0-SNAPSHOT.1477-

Thanks for reading.

This is an issue with WorldGuard. They changed how the use flag works. I had to replace use: deny to use: null in the region file.