In Beyond use Better Chunk Loaders for chunkloading instead!

To claim an area open your inventory and click the map icon

Then just click the chunk on the map

to chunkload the chunk SHIFT+LEFTCLICK the claimed chunk

To unclaim an area just RIGHTCLICK a claimed chunk

IN NEWER VERSIONS THIS IS REPLACED BY THE TEAM GUI ON THE LEFT FROM YOUR INVENTORY

To give your friends access to your claimed chunks invite them with this command
/team invite <username>

After you invited your friend, he/she has to run
/team join <yourname>

If your friend is already in a team, he/she can leave it with
/team leave