Cannot sectorize terrain

[cgrahamseven]

I have a large world map that I am wanting to stream with SECTR. Each tile is a Unity terrain of 256x256 units. Overall I have a world map grid that is  essentially made up of 27 tiles along the x axis and 21 tiles along the y axis. So 567 tiles altogether. When I open up the SECTR terrain window to sectorize the terrains, anytime I select one of the terrains and click the sectorize terrain button, it adds a sectr component to the terrain but then spits out a warning message in console stating that it cannot sectorize a terrain that is already part of a sector. 

Going back and reviewing videos of people sectorizing large terrain, I noticed that they start out with a single large unity terrain and break that up into sectrs. My terrain is already split into individual tiles that I want to be sectrs. So in the options for the SECTR terrain window I have de-selected Split Terrain and set number of sectors to: per width: 1, per length: 1, per height: 1. 

The documentation doesn't really have any specifics on how to handle my scenario. I have reviewed both the full documentation and the quick start guide. 

Also, is there a way to shift-select all of the terrain in the SECTR terrain window so I don't have to manually select all 567 tiles to sectorize them?

[Bryan]

Are you using Gaia's world streaming and multi-terrain creation or is this standard Unity?