OK, answering my own question...
Here are errata for the location numbers in the Messantia Game Master's Guide:
Mongoose folks, if you're reading, feel free to make it "official", I can't be the only person who's been confused by this
Dustbiter (p.10-11)
All numbering correct.
Dockside (p.13-17)
All numbering correct.
Bazaar Prefect (p.18-20)
Correct up to:
91 Nine Smoke Rings
92 Labrencis' Market (merged into entry above)
93 Finely Shorn
94 Palace Patrol Station
95 Fluvio's Timepieces
96 The Bronze Idol
97 The Fighting Bull
98 Domenico's Fine Leathers
99 Healing Hands
100 Varian's Meats
101 The Sturdy Shoe
102 Miklus' Garden
103 Linia's Clothiers
104 Ristoro's Gallery
105 The Marble Hearth
106 Bathhouse
107 Tides of Time
108 The Perfect Touch
109 Weavings
110 Vintage Taste
111 Divine Delight
112 The Fox Afoot
113 Aldiana's Grace
114 Spun Silk
River Prefect (p.20-22)
115 The Last Laugh
116 Domingo Arkashan's Proving Ground
117 Five Harts
118 The Silver Shark
119 The Anvil's Edge
120 Giuseppe's Fine Cauldrons
121 Malatesta Porters
122 The Bulwark
123 Born of Steel
124 Prefect Patrol Station
125 A Place for Everything
126 Spun of Clay
127 Boon of Health
128 Rosanos Instruments
129 Traders' Hearth
130 Cosimo's Seconds
131 The Golden City
132 Pointed Words (Description missing)
133 Alamanno's
134 Alesso's Market
135 Labourers' Rest
136 Giusto's Oven
137 Leather and Mail
138 The Coin's Edge
Arena Prefect (p.25-26)
139 The Arena
140 Arena's Favour
141 Tavern of Trials
142 The Great Contest
143 The Lazy Dragon
144 Prefect Patrol Station
145 Rental House
146 Rental House
147 The Golden Pheasant
148 Statue of Captain Stroza
149 The King's Table
150 Rental House
151 Rental House
152 Bathhouse
153 Meticulous Care
154 Sundries
155 Rental House
156 The Loom's Art
157 The Broken Trumpet
158 Rental House
159 The Noble Gentleman
160 Statue of Demetrius (description missing)
161 Rental House
162 The Finest Art
163 Bathhouse
164 The Finishing Touch
King's Prefect (p.27-29)
165 Santi's
166 The Sated Lion
167 Rare Imports
168 Bathhouse
169 Temple of Mitra
170 House Onoria villa
171 House Gilroy villa
172 House Tarchon villa
173 House Loreca villa
174 Bathhouse
175 Ruberta's
176 Impassable Fastenings
177 Prefect Patrol Station
178 Taddeo's Taste (description missing)
179 House Pluvius villa
180 House Eurus villa
181 House Abasantis villa
182 House Florens villa
183 House Drusus villa
184 House Gabrio villa
185 Temple of Trade
186 Lapo's Creations (printed out of sequence, should be after Temple of trade on p.27)
187 Bathhouse
188 House Pompilius villa
189 House Corvara villa
190 House Idaeus villa
191 The Palace
192 Good Fortune (description missing)
193 House Tullus villa
194 House Pephredo villa
195 House Brencis villa
196 House Dulcia villa
197 Bathhouse
198 Pancia's Pastries and Confections
199 House Mycaelis villa
200 House Anchises villa
201 House Mazentius villa
202 House Actaeus villa
203 Vigour
204 Sanella's
205 Envoy of Shem
206 Envoy of Zingara
207 Envoy of Aquilonia
208 Envoy of Nemedia
209 Envoy of Koth
210 Envoy of Ophir
211 Plaza of the People
212 The Dome of the Sea
213 The Plazas
214 Magistrate Hall and Mariners' Plaza
215 Central Tariff Office
216 Palace Patrol Station
217 Central Licensing Office
218 Order of Engineers
219 Clockmakers Guild
220 Musicians Guild
221 Blacksmiths Guild
222 Caravaners Guild
223 Shipwrights Guild
224 Street Sweepers Guild
225 Clothiers Guild
226 Hostellers Guild
227 Porters Guild
228 Fishermans Guild
229 Shipmasters Guild
230 Finesmiths Guild
231 Butchers Guild
232 Sewer Workers Guild
233 Lucius Stage
Hilltop Prefect (p.30-31)
234 Publio's villa
235 House Fendio villa
236 The Graneries
237 The Shipyards
Cranetown (p.34)
238 Parsion's Statue
239 Bargehold
240 The Cisterns
241 Seven Stilts
242 Conclave
243 Healing Sea
244 The Shark's Bite
245 The Sea Urchin
246 Ladies of the Waves
247 Fish and Tack
248 A Taste of Land
249 Four Masts Tavern
250 The Laughing Swordfish
