There are a few things wrong here; I'll just go over them as I see them and identify the root of the problem when I see it:
[TILE:263C]
Evident typo
[BIOME:ANY_MAIN]
ANY_MAIN is not a biome type - you're thinking of ALL_MAIN, but keep in mind that that covers bodies of water as well. ANY_LAND might be a better choice. Regardless, it's not altogether desirable to give your civ creatures a biome tag - they won't need it, unless you're making a deliberate effort to spawn wild ones as well (in which case just adding the biome tag won't cut it).
[MEANDERER]
I'm not sure what effect this would have on gameplay. MEANDERER usually just makes things move in semirandom directions... it might interfere with pathfinding.
[SELECT_SYMBOL:EARTH:NAME_EARTH]
Symbols don't quite work like that, but the mistake's definitely understandable. The first variable field shows
what the civ is going to be assigning the symbol to - ALL, WAR, BATTLE, SIEGE, CIV, SITE, ROAD, TUNNEL, BRIDGE, WALL and REMAINING (ie, anything that's not covered by anything else). The second field is the symbol class itself, a list of which can be found in language_SYM.txt in your raws directory.
~ninja'd, skipping some things that have been covered
[DEFAULT_SITE_TYPE:MOUNTAIN]
This needs to be DARK_FORTRESS, CAVE, CAVE_DETAILED, CITY, TREE_CITY or RUIN. Also note that some site types only work on some biomes (tree cities only work on forests, etc).