Between <GameData> and <Row> you are missing the <Buildings> tag.
Don't forget to close that tag also after your </Row> Tag.
As I said in the original post, <Buildings> tags are already included within the CIV5Buildings document I copied over, just as <Game Data> tags are already there. That is why I didn't copy them when I copied the code into my post. Those tags are hundreds and hundreds of lines away from the Palisades data, with dozens of other Buildings table entries between them and the <Row> tag that encloses my Palisades data.
Or are you saying that when you add a new building that there has to be a second and unique <Building> tag that goes just around that new building, like this:
<Game Data>
<Building>
<Row>
<Type>BUILDING_GRANARY</Type>
.
.
.
</Row>
<Row>
<Type>BUILDING_MARKETPLACE</Type>
.
.
.
</Row>
<Row>
<Type>BUILDING_SEAPORT</Type>
.
.
.
</Row>
<Building>
<Row>
<Type>BUILDING_PALISADE</Type>
<BuildingClass>BUILDINGCLASS_PALISADE</BuildingClass>
<Cost>60</Cost>
<GoldMaintenance>1</GoldMaintenance>
<Help>TXT_KEY_BUILDING_PALISADE_STRATEGY</Help>
<Description>TXT_KEY_BUIDING_PALISADE</Description>
<Civilopedia>TXT_KEY_CIV5_BUILDINGS_PALISADE_TEX T</Civilopedia>
<Strategy>TXT_KEY_BUILDING_PALISADE_STRATEGY</Strategy>
<ArtDefineTag>ART_DEF_BUILDING_WALLS</ArtDefineTag>
<MaxStartEra>ERA_ANCIENT</MaxStartEra>
<MinAreaSize>-1</MinAreaSize>
<AllowsRangeStrike>true</AllowsRangeStrike>
<Defense>250</Defense>
<CityWall>true</CityWall>
<HurryCostModifier>25></HurryCostModifier>
<IconAtlas>BW_ATLAS_1</IconAtlas>
<NeverCapture>true</NeverCapture>
<PortraitIndex>32</PortraitIndex>
</Row>
</Building>
<Row>
<Type>BUILDING_WALLS</Type>
.
.
.
</Building>
</Game Data>
If so, why? Why does there have to be a nested <Building> tag inside the<Building> tags that enclose all the buildings in the xml document?