diff --git a/docs/GAUGE_COMPOSITE.md b/docs/GAUGE_COMPOSITE.md
index 2efff28..8c8ebbc 100644
--- a/docs/GAUGE_COMPOSITE.md
+++ b/docs/GAUGE_COMPOSITE.md
@@ -220,3 +220,47 @@ yet reconstructed (parse-skipped). The separate window is now the **live viewer*
   monitors. NOT a CFG rename (the CFG uses BT names pervasively + `MUNGA_L4` is shared with RP's aux names).
 - **Polish:** overlay-plane compositing over `sec`; a pod-accurate RGB-packing toggle; texture atlas
   (one lock/upload); device-reset recreate hardening for the additional swap chain.
+
+## Widget reconstruction — the real fix (in progress; mapped by `bt-gauge-widget-recon-map`)
+
+**Why the surfaces show only frames:** the BT gauge method table `BTL4MethodDescription[]` (btl4grnd.cpp)
+was a chain-only STUB, and **no BT gauge class registered a `methodDescription`**, so every BT-specific gauge
+keyword (`cmHeat`/`headingPointer`/`map`/`vertBar`/`GeneratorCluster`/…) failed table lookup and was
+parse-skipped. The binary's real table @0x51c910 has 23 gauge entries; 19 keywords are actually invoked by
+this CFG. The reconstructed classes exist in `btl4gaug/gau2/gau3.cpp` but most have prose-only (undefined)
+ctors/Execute/connection-feeds — only a few chains are fully real code.
+
+**The registration recipe (per widget, mirrors the engine — `NumericDisplayScalar`, L4GAUGE.cpp:542):**
+1. Add `static MethodDescription methodDescription;` to the class in its `.hpp`.
+2. Define `<Class>::methodDescription = { "cfgKeyword", <Class>::Make, { {type,NULL}…, PARAMETER_DESCRIPTION_END } }`
+   in the class's `.cpp`. **The param-type list MUST match the binary's `.data` exactly** — the parser reads
+   one token per entry to the `typeEmpty` terminator (GAUGREND.cpp:1458); a wrong count desyncs the parse.
+3. Rewire `Make` to read `methodDescription.parameterList[]` (the interpreter restores each instance's parsed
+   params there before calling Make) instead of placeholder statics; the runtime port arg (`display_port_index`)
+   is the graphics port, NOT a param slot.
+4. Register `&<Class>::methodDescription` in `BTL4MethodDescription[]` (btl4grnd.cpp), **chain link LAST**.
+
+**⚠ THE /FORCE TRAP (the load-bearing gotcha): register a widget ONLY when its whole Make→ctor→feed→every-
+vtable-slot chain is REAL code.** A registered class instantiates its vtable; any prose-only/undefined virtual
+(dtor, `BecameActive`, a connection ctor) is `/FORCE`-stubbed to the image base and AVs the moment it's called.
+The build "succeeds" (exit 0) and lies — **grep the link log for `unresolved external` on the class's symbols**
+(filter out the known dead `mech3.obj` `DefaultData`/`CreateStreamedSubsystem` offline-factory externals).
+
+**✅ Increment 1 — `cmHeat` (ColorMapperHeat) DONE (commit pending).** The first registered BT gauge widget.
+Pure wiring proved the whole pipeline: added the `methodDescription` (`R,Md,C,St,St,St`, keyword `cmHeat`),
+rewired `Make` to `parameterList[]`, registered it. Registering it EXPOSED two `/FORCE`-stubbed real functions
+in the chain (the map had missed them) — reconstructed both from the decomp: `ColorMapper::BecameActive`
+(@004c395c — invalidates the cached colour index + last RGB so the next Execute re-pushes the palette) and
+`ColorMapperHeat::~ColorMapperHeat` (empty — base chain releases the HeatConnection + palettes). Verified:
+register→parse→Make→ctor→`FindSubsystem("GeneratorA")` (resolves — no "does not exist")→HeatConnection→
+Execute→palette-push runs end-to-end; combat un-regressed (TARGET DESTROYED, 0 crashes); the sec/heat
+schematic zones are now tinted by the REAL subsystem `currentTemperature` (stable tint since temp is stable —
+the visible-animation win is `headingPointer` next). **Method established for every remaining widget.**
+
+**Next increments (priority order from the map):** `headingPointer` (rotating compass + numeric heading —
+reconstruct from prose `btl4gaug.cpp:644`, reads owner quaternion directly, no attribute table/connection
+needed — the visible money-shot); then `cmArmor`/`colorMapperMultiArmor` (armor schematic, needs the
+`ArmorZoneConnection`/`MultiArmorConnection` classes reconstructed); then the attribute-table wave (`vertBar`/
+`segmentArcRatio` speed/`GeneratorCluster` — need `AttributePointers[]` on Mech/HeatableSubsystem, a separate
+pass); the XL items (`map`/`vehicleSubSystems`/`PlayerStatus`) last. The POD path needs the FULL 23-entry
+table with real ctors (the dev tolerant-skip is the on-ramp, not the finish).
diff --git a/game/reconstructed/btl4gaug.cpp b/game/reconstructed/btl4gaug.cpp
index d3fd78c..4ab72c1 100644
--- a/game/reconstructed/btl4gaug.cpp
+++ b/game/reconstructed/btl4gaug.cpp
@@ -304,6 +304,20 @@ ColorMapper::~ColorMapper()
 	// base ~Gauge -- FUN_00444360
 }
 
+//
+// @004c395c -- ColorMapper::BecameActive.  On (re)activation, force the next
+// Execute (@004c3980) to re-push the hardware palette: invalidate the cached
+// colour index + the last-written RGB so the "unchanged" fast-out can't skip the
+// write (the surface may have been cleared/redrawn while the gauge was inactive).
+//
+void
+	ColorMapper::BecameActive()
+{
+	currentColorIndex  = -1;			// this[0x15] @0x54
+	previousColorIndex = -1;			// this[0x16] @0x58
+	previousRed = previousGreen = previousBlue = 0xFF;	// this[0x19] @0x64-0x66
+}
+
 //
 // @004c3980 -- the palette push.  Clamp the driving value to a [0,255] colour
 // index, choose the active palette (flashing alternates the two when
@@ -423,41 +437,57 @@ void
 // DAT_00515020 port, DAT_00515064/0a8/0ec palette/slot/subsystem-name) and the
 // class name "ColorMapperHeat" (0x5184c4).
 //
+
 //
-// Unrecovered .data resource pool used by ColorMapperHeat::Make (the gauge's
-// configured rate/mode/port/colour/palette names).  The concrete bytes were not
-// recovered from the optimised image; declared here as typed placeholders so the
-// construction path compiles.  (BEST-EFFORT -- real values live in l4gauge.cfg.)
+// The gauge's configured parameters come LIVE from the config interpreter (the
+// CFG "cmHeat" primitive) via methodDescription.parameterList -- the interpreter
+// restores each instance's parsed params into this scratch list before calling
+// Make (the engine pattern, cf. NumericDisplayScalar::Make L4GAUGE.cpp:569).
+// The earlier DAT_* placeholders (unrecovered .data) are gone.
+// CFG shape (verified L4GAUGE.CFG:182):
+//    cmHeat( rate, modeMask, colourSlot, paletteA, paletteB, subsystemName )
+//    e.g.   cmHeat(H, ModeSecondaryHeat, 32, heatpal.pcc, heatpal2.pcc, GeneratorA);
 //
-static int  DAT_00514f98 = 0;	// GaugeRate
-static int  DAT_00514fdc = 0;	// ModeMask
-static int  DAT_00515020 = 0;	// graphics port number
-static int  DAT_00515064 = 0;	// colour-slot resource (&-taken)
-static char DAT_005150a8[] = "";	// palette name A
-static char DAT_005150ec[] = "";	// palette name B
+MethodDescription
+	ColorMapperHeat::methodDescription =
+	{
+		"cmHeat",
+		ColorMapperHeat::Make,
+		{
+			{ ParameterDescription::typeRate,     NULL },	// refresh-rate ID
+			{ ParameterDescription::typeModeMask, NULL },	// display mode mask
+			{ ParameterDescription::typeColor,    NULL },	// hardware colour slot
+			{ ParameterDescription::typeString,   NULL },	// palette name A
+			{ ParameterDescription::typeString,   NULL },	// palette name B
+			{ ParameterDescription::typeString,   NULL },	// heat subsystem name
+			PARAMETER_DESCRIPTION_END
+		}
+	};
 
 Logical
 	ColorMapperHeat::Make(
-		int					/*display_port_index*/,
+		int					display_port_index,
 		Vector2DOf<int>		/*position*/,
 		Entity				*entity,
 		GaugeRenderer		*gauge_renderer
 	)
 {
+	ParameterDescription *p = methodDescription.parameterList;
+
 	ColorMapperHeat *gauge =
 		(ColorMapperHeat *)operator new(0x6c);		// FUN_00402298(0x6c)
 	if (gauge != NULL)
 	{
 		new (gauge) ColorMapperHeat(				// FUN_004c3f6c
-			(GaugeRate)DAT_00514f98,
-			(ModeMask) DAT_00514fdc,
+			p[0].data.rate,					// rate ID
+			p[1].data.modeMask,				// mode mask
 			(L4GaugeRenderer *)gauge_renderer,
-			DAT_00515020,					// graphics port number
-			(int)&DAT_00515064,				// colour slot resource
+			display_port_index,				// graphics port number (the runtime port)
+			p[2].data.color,				// colour slot
 			entity,
-			(char *)&DAT_005150a8,			// palette name A
-			(char *)&DAT_005150ec,			// palette name B
-			(char *)"ColorMapperHeat",		// subsystem name resource / id
+			p[3].data.string,				// palette name A
+			p[4].data.string,				// palette name B
+			p[5].data.string,				// heat subsystem name (e.g. "GeneratorA")
 			"ColorMapperHeat");
 	}
 	return True;
@@ -524,6 +554,17 @@ ColorMapperHeat::ColorMapperHeat(
 	AddConnection(connection);						// (*this+0x34)
 }
 
+//
+// ColorMapperHeat destructor.  No extra work: the HeatConnection added above is
+// released by the base Gauge teardown (RemoveAllConnections), and the two
+// palettes by ~ColorMapper -- so the base-dtor chain (~ColorMapper -> ~Gauge)
+// runs implicitly at the closing brace.  (The binary's deleting-dtor thunks
+// @004c66ff/6725/674b/6771 forward to that same base chain.)
+//
+ColorMapperHeat::~ColorMapperHeat()
+{
+}
+
 
 //###########################################################################
 //###########################################################################
diff --git a/game/reconstructed/btl4gaug.hpp b/game/reconstructed/btl4gaug.hpp
index 84a359d..86476ad 100644
--- a/game/reconstructed/btl4gaug.hpp
+++ b/game/reconstructed/btl4gaug.hpp
@@ -202,6 +202,10 @@
 			Entity *, const char *, const char *,
 			const char *heat_subsystem_name, const char *);
 		~ColorMapperHeat();
+
+		// Registered in BTL4MethodDescription[] (btl4grnd.cpp) so the config
+		// interpreter builds this gauge from the CFG "cmHeat" primitive.
+		static MethodDescription methodDescription;
 	};
 
 
diff --git a/game/reconstructed/btl4grnd.cpp b/game/reconstructed/btl4grnd.cpp
index 06b7fd0..ce5b2ed 100644
--- a/game/reconstructed/btl4grnd.cpp
+++ b/game/reconstructed/btl4grnd.cpp
@@ -120,6 +120,16 @@ extern
 MethodDescription
 	*BTL4MethodDescription[] =
 		{
+			//
+			// BT gauge WIDGET reconstruction -- register each BT-specific gauge
+			// class's methodDescription so the config interpreter can build it
+			// (the CFG keyword -> class Make).  Add ONE at a time, only when its
+			// whole Make->ctor->feed chain is REAL code (a prose-only/undefined
+			// link would be /FORCE-stubbed and AV at runtime; see CLAUDE.md §10).
+			// The chain-to-previous link MUST stay LAST (routes unmatched keywords
+			// to the engine base table L4MethodDescription).
+			//
+			&ColorMapperHeat::methodDescription,	// "cmHeat" -- heat-driven palette tint
 			&BTL4ChainToPrevious
 		};