The Open Creative world was an idea of having a Creative world that lacked any plot system, and was just an open flat world for players to build larger structures. It was inspired by a similar feature that Nuclear District had in 2015 when CU and ND first merged, but didn't last long due to difficulties in preventing grief. Shortly after this, the decision was made to increase plot sizes to the larger 199x199 size.
You cannot take this map, or any structures within it, and run it in your own server or someone else's. This is only for those who wants to continue their projects on it instead of having to start over in single player mode. Breaking this rule will result in your download privileges being permanently suspended and could result in your account being banned.