diff --git a/game/reconstructed/btl4gaug.cpp b/game/reconstructed/btl4gaug.cpp
index dc618c5..923dfb2 100644
--- a/game/reconstructed/btl4gaug.cpp
+++ b/game/reconstructed/btl4gaug.cpp
@@ -1703,21 +1703,40 @@ void BitMapInverseWipe::BecameActive()			// @004c5cf4
 }
 
 //
-// @004c5d08 -- Execute.  BRING-UP: the authentic wipe (reveal the bitmap columns
-// up to the level, coloured by colorA/colorB) needs the frame-strip blit math;
-// a safe minimal repaint (blit the base frame on level change) keeps the vtable
-// complete + non-crashing until the full wipe lands.
+// @004c5d08 -- Execute.  Round the level to [0, fullWidth] (a tiny non-zero value
+// forces at least 1); on a change repaint `frames` segments stacked vertically,
+// each picking its strip frame from the level: <1 = empty (colorA, frame 0), ==1 =
+// half (colorB, middle frame), >1 = full (colorB, last frame), decrementing the
+// level by 2 per segment.  (The coolant LeakGauge; value = CoolantMassLeakRate.)
 //
 void BitMapInverseWipe::Execute()
 {
-	int level = (int)value;
+	int level = (int)(value + (value < 0.0f ? -0.5f : 0.5f));	// FUN_004dcd94 round
+	if (level < 0)          level = 0;
+	if (level > fullWidth)  level = fullWidth;
+	if (value > 0.0025f && level < 1)  level = 1;				// _DAT_0050e3d8
+
 	if (level != previousLevel)
 	{
 		previousLevel = level;
 		L4Warehouse *warehouse = (L4Warehouse *)renderer->warehousePointer;
 		BitMap *bmp = warehouse->bitMapBin.Get(imageName);
 		if (bmp != NULL)
-			localView.DrawBitMapOpaque(0, 0, bmp);
+		{
+			int y = -frameHeight;
+			for (int seg = frames; seg > 0; seg--)
+			{
+				localView.MoveToAbsolute(0, y);					// vtbl+0x24
+				int frameIndex;
+				if (level < 1)			{ localView.SetColor(colorA); frameIndex = 0; }
+				else if (level == 1)	{ localView.SetColor(colorB); frameIndex = frameWidth; }
+				else					{ localView.SetColor(colorB); frameIndex = frameWidth * 2; }
+				localView.DrawBitMap(0, bmp, frameIndex, 0,		// vtbl+0x54
+					frameWidth + frameIndex, frameHeight);
+				level -= 2;
+				y    -= frameHeight;
+			}
+		}
 		warehouse->bitMapBin.Release(imageName);
 	}
 }