The default Garden of Gaia wasn't generating very well (the central lake kept drying out), so I removed the map and simply kpt the settings for a random world, maybe it'll be useful to someone:
[WORLD_GEN]
[TITLE:COPY]
[CUSTOM_NAME:Garden of Gaia]
[DIM:65:65]
[EMBARK_POINTS:1274]
[END_YEAR:100]
[BEAST_END_YEAR:100:80]
[REVEAL_ALL_HISTORY:1]
[CULL_HISTORICAL_FIGURES:0]
[ELEVATION:1:400:1000:1000]
[RAINFALL:0:100:3200:3200]
[TEMPERATURE:30:50:1000:999]
[DRAINAGE:0:100:1000:1000]
[VOLCANISM:0:100:3200:3200]
[SAVAGERY:0:100:3200:3200]
[ELEVATION_FREQUENCY:1:0:0:0:0:0]
[RAIN_FREQUENCY:1:1:1:1:1:1]
[DRAINAGE_FREQUENCY:1:1:1:1:1:1]
[TEMPERATURE_FREQUENCY:1:1:1:1:1:1]
[SAVAGERY_FREQUENCY:1:1:1:1:1:1]
[VOLCANISM_FREQUENCY:1:1:2:3:4:5]
[MINERAL_SCARCITY:100]
[MEGABEAST_CAP:50]
[SEMIMEGABEAST_CAP:50]
[TITAN_NUMBER:100]
[TITAN_ATTACK_TRIGGER:30:0:0]
[DEMON_NUMBER:22]
[NIGHT_TROLL_NUMBER:26]
[BOGEYMAN_NUMBER:26]
[VAMPIRE_NUMBER:26]
[WEREBEAST_NUMBER:26]
[SECRET_NUMBER:52]
[REGIONAL_INTERACTION_NUMBER:52]
[DISTURBANCE_INTERACTION_NUMBER:52]
[EVIL_CLOUD_NUMBER:26]
[EVIL_RAIN_NUMBER:26]
[GOOD_SQ_COUNTS:555:222:0]
[EVIL_SQ_COUNTS:555:222:0]
[PEAK_NUMBER_MIN:10]
[PARTIAL_OCEAN_EDGE_MIN:0]
[COMPLETE_OCEAN_EDGE_MIN:0]
[VOLCANO_MIN:0]
[REGION_COUNTS:SWAMP:0:0:0]
[REGION_COUNTS:DESERT:0:0:0]
[REGION_COUNTS:FOREST:0:0:0]
[REGION_COUNTS:MOUNTAINS:0:0:0]
[REGION_COUNTS:OCEAN:0:0:0]
[REGION_COUNTS:GLACIER:0:0:0]
[REGION_COUNTS:TUNDRA:0:0:0]
[REGION_COUNTS:GRASSLAND:0:0:0]
[REGION_COUNTS:HILLS:0:0:0]
[EROSION_CYCLE_COUNT:0]
[RIVER_MINS:400:400]
[PERIODICALLY_ERODE_EXTREMES:1]
[OROGRAPHIC_PRECIPITATION:1]
[SUBREGION_MAX:5000]
[CAVERN_LAYER_COUNT:3]
[CAVERN_LAYER_OPENNESS_MIN:85]
[CAVERN_LAYER_OPENNESS_MAX:100]
[CAVERN_LAYER_PASSAGE_DENSITY_MIN:0]
[CAVERN_LAYER_PASSAGE_DENSITY_MAX:10]
[CAVERN_LAYER_WATER_MIN:20]
[CAVERN_LAYER_WATER_MAX:50]
[HAVE_BOTTOM_LAYER_1:1]
[HAVE_BOTTOM_LAYER_2:1]
[LEVELS_ABOVE_GROUND:15]
[LEVELS_ABOVE_LAYER_1:10]
[LEVELS_ABOVE_LAYER_2:5]
[LEVELS_ABOVE_LAYER_3:5]
[LEVELS_ABOVE_LAYER_4:5]
[LEVELS_ABOVE_LAYER_5:2]
[LEVELS_AT_BOTTOM:1]
[CAVE_MIN_SIZE:25]
[CAVE_MAX_SIZE:50]
[MOUNTAIN_CAVE_MIN:50]
[NON_MOUNTAIN_CAVE_MIN:50]
[ALL_CAVES_VISIBLE:1]
[SHOW_EMBARK_TUNNEL:2]
[TOTAL_CIV_NUMBER:20]
[TOTAL_CIV_POPULATION:15000]
[SITE_CAP:1000]
[PLAYABLE_CIVILIZATION_REQUIRED:1]
[ELEVATION_RANGES:0:0:0]
[RAIN_RANGES:0:0:0]
[DRAINAGE_RANGES:0:0:0]
[SAVAGERY_RANGES:0:0:0]
[VOLCANISM_RANGES:0:0:0]
I wouldn't mind any suggestion on fixing the lake, too.