The tracks were never built from one model

A map record is an Entity::MakeMessage (MUNGA/ENTITY3.h): classToCreate,
owningPlayerID, resourceID, instanceFlags, localOrigin. The origin ends
the 76-byte case, which puts classToCreate at +28, resourceID at +40 and
instanceFlags at +44.

I had been reading +44. That is instanceFlags, and it is 524 on every
scenery record - and 524 happens to be cn3's GaugeImage. So every track
resolved to cn3 repeated a few hundred times, consistently and wrongly,
and every conclusion drawn from that followed: the "one wall bar with a
gate", the ticks, the claim that the LOD machinery is never exercised.

The id at +40 varies per placement. The tracks use cn1, cn3, cn4, cn5,
cn7, br1, br3, ft1, cq1, cq2, md3, md4, the pits, and the score zones
sc50/sc50a/sc500a that gave the amber boxes at each end. A record names
the model's Model List; the GaugeImage is filed under the same model
name, so the name is the join - and models with no gauge image (oao,
snAwork, pz1) are skipped here exactly as DrawStatic skips them.

Found by following the map loader: InterestManager::LoadMapStream reads
the stream as MakeMessages and names the map entity classes, one of which
is 95 in these records - CulturalIconClassID.

tools/mapview/build_mapview.py

@@ -97,6 +97,10 @@ xml = open(ROOT + '/tools/console-config/RPConfig.xml', encoding='utf-8-sig').re
 for m in re.finditer(r'<map\s+key="([^"]+)"\s+name="([^"]+)"', xml):
     CONSOLE[m.group(1)] = m.group(2)
 
+# A record names the model's Model List; its GaugeImage is filed under the
+# same model name. navmap.gauge_lookup does that join.
+LOOKUP = {k: v for k, v in navmap.gauge_lookup(TABLE).items() if v in images}
+
 tracks = []
 for rid, r in sorted(TABLE.items()):
     m = re.match(r'^(\w+): Map stream of (\d+) instances$', r['desc'])
@@ -105,9 +109,9 @@ for rid, r in sorted(TABLE.items()):
     key, count = m.group(1), int(m.group(2))
     placed, noart = [], 0
     for gid, pos, q in navmap.instances(RES, r['addr'], r['size'], count,
-                                        set(images)):
+                                        LOOKUP):
         if gid is None:
-            noart += 1                           # the map screen skips these
+            noart += 1              # no gauge image: the map skips these too
             continue
         placed.append([gid,
                        round(pos[0], 2), round(pos[1], 2), round(pos[2], 2),