Oh also, if your inventory is full during a vote party.... it says "Your voter crate key was dropped in front of you". The key is there on the ground but the grass blocks aren't. This has happened to me countless times.
I can build anywhere outside of my island as long as I am physically inside the area where I can build. E.G there is a wall just outside my island which I can break and destroy if I am inside the build area. (Note not sure if it only works for mods or not)
There have also been problems with /seen as far as I know. Apparently, some players are exempt from being /seen by any other player. Even if you got his/her name correctly (Adding in that no name change was done) there is an error saying "This player cannot be found". It might be an issue with some people and not all, but it would be good to check this out as well.
From what I've tested players can eat food on others island, but they mustn't be looking/targeting a block, chest, slab, etc. Also, I believe that either the island protection isn't correctly placed as on 2 sides you can build from bedrock 50 blocks and on the other 2 you can build 48 blocks or the bedrock/island/Skyblock isn't centered.
At spawn, you are told that you cannot use the /lock command, yet it still says that your island was locked. This doesn't happen with /unlock; you are only told that you can't use the command.
I've found that I can't eat while flying in someone else's territiory, but as soon as I land on a block, I can often eat with no problems.
This happens to me...except vice virsa. The only way for my to eat (Sometimes) is when Im in the air and away from a block's radius. (ie. can stand next to/on fences)
Tanner, very very important, not being able to do on other peoples islands is GOOD. Think of the pain it will cost the mods! The killing will be real. Do not change this.