Naga citadel is the upgrade for the bulding. So, if you take human town hall (and keep, and castle) and change its model to this one here that u downloaded, townhall model will be temple of tides, and keep model will be Naga Citadel, I think
and so on
(as you can see in warcraft, townhall, keep, and castle all have same models, but keep is stand upgrade 1, and castel is stand animation of upgrade 2, or something)