Ellias is correct for Faction building permissions, but the design you asked about is here:Edited By: Skeltsco Ofsseto on Year 12 Day 38 23:43
In the city design page, there is a input out put for a URL (lower right hand corner)...
Design a city, lay down the facils and buildings, then Click the URL "OUTPUT" it gives the city layout in a PHP? number design, something like this Http://swcombine/citydesign/v2.v4v5v4v4v7v9v9v7v56v4v3v3v5v7v9v9v...ect
That is a city design code, copy and paste it, then send it to the faction you are asking for permission to build.
A faction will look it over (Copy and Paste it back into the box, click "IN" in the city design box again(from a faction or you), it shows the lay out of that city you just made) and see if there is the right amount of jobs vs flats. If they see it's correct then you use that plan to build a city once permission is given.
Hope that helps.
edited for clerifactions
Recruiter for Black Nebula Engineering.