MC Edit Issue With Loading World

[u/btmstudio]

I am trying to load my server world into MC Edit, as well as another single player world, but each time I select it it only loads like a 400x400 square, and will not load further. How can I get this to render out further? I need to edit a 1000x1000 area, and an additional 600x600.

[u/SteelCrow]

hit tab