diff --git a/polymer/eduke32/build/include/editor.h b/polymer/eduke32/build/include/editor.h
index 7582dfcb2..bd8a9e0af 100644
--- a/polymer/eduke32/build/include/editor.h
+++ b/polymer/eduke32/build/include/editor.h
@@ -461,6 +461,8 @@ FORCE_INLINE void inpclamp(int32_t *x, int32_t mi, int32_t ma)
 
 #define drawtranspixel(p, col) drawpixel(p, blendtable[0][(readpixel(p) * 256) + col])
 
+// Timed offset for Mapster32 color index cycling.
+// Range: 0 .. 16
 #define M32_THROB klabs(sintable[((totalclock << 4) & 2047)] >> 10)
 
 #ifdef __cplusplus
diff --git a/polymer/eduke32/build/src/build.c b/polymer/eduke32/build/src/build.c
index c4eee496c..6aaf32cbf 100644
--- a/polymer/eduke32/build/src/build.c
+++ b/polymer/eduke32/build/src/build.c
@@ -3291,8 +3291,11 @@ static void drawspritelabel(int i)
 
 //    int const blocking = (sprite[i].cstat & 1);
 
+    // KEEPINSYNC drawscreen_drawsprite()
     uint8_t const spritecol = spritecol2d[sprite[i].picnum][0];
-    int col = spritecol ? editorcolors[spritecol] : getspritecol(i);
+    uint8_t const blockingSpriteCol = spritecol2d[sprite[i].picnum][1];
+    int col = spritecol ? editorcolors[(sprite[i].cstat&1) ? blockingSpriteCol : spritecol] :
+        getspritecol(i);
 
     if (show2dsprite[i>>3]&pow2char[i&7])
         col = editorcolors[14] - (M32_THROB>>1);
@@ -3759,7 +3762,7 @@ void overheadeditor(void)
                                     }
 
                                     drawlinebetween(&v1, &v2, !hlp ? 8 :
-                                                    editorcolors[wal->nextwall >= 0 ? 33 : 7],
+                                                    editorcolors[wal->nextwall >= 0 ? 12 : 7],
                                                     0x11111111);
                                 }
                             }
diff --git a/polymer/eduke32/build/src/engine.c b/polymer/eduke32/build/src/engine.c
index 34e9897eb..c5b65c546 100644
--- a/polymer/eduke32/build/src/engine.c
+++ b/polymer/eduke32/build/src/engine.c
@@ -17320,11 +17320,12 @@ static void drawscreen_drawsprite(int32_t j, int32_t posxe, int32_t posye, int32
     int col;
 
     const spritetype *const spr = &sprite[j];
-    int16_t const hitblocking = (spr->cstat&256);
+    int16_t const blocking = (spr->cstat&1), hitblocking = (spr->cstat&256);
     int16_t const flooraligned = (spr->cstat&32), wallaligned = (spr->cstat&16);
 
     int16_t const angofs = m32_sideview ? m32_sideang : 0;
 
+    // KEEPINSYNC build.c: drawspritelabel()
     if (spr->sectnum<0)
         col = editorcolors[4];  // red
     else
@@ -17332,16 +17333,9 @@ static void drawscreen_drawsprite(int32_t j, int32_t posxe, int32_t posye, int32
         uint8_t const spritecol = spritecol2d[spr->picnum][0];
 
         if (spritecol)
-            col = spritecol;  // XXX: should be editorcolors[spritecol]
+            col = editorcolors[blocking ? spritecol2d[spr->picnum][1] : spritecol];
         else
             col = getspritecol(j);
-#if 0
-        else if (spr->cstat&1)
-        {
-            uint8_t const blockingSpriteCol = spritecol2d[spr->picnum][1];
-            col = blockingSpriteCol ? blockingSpriteCol : 5;
-        }
-#endif
     }
 
     if (editstatus == 1)
@@ -17356,12 +17350,7 @@ static void drawscreen_drawsprite(int32_t j, int32_t posxe, int32_t posye, int32
         else // if (highlightcnt > 0)
         {
             if (show2dsprite[j>>3]&pow2char[j&7])
-            {
-                col = editorcolors[14];
-
-//                if ((totalclock & 16) == 0)
-                    col -= (M32_THROB>>1);
-            }
+                col = editorcolors[14] - (M32_THROB>>1);
         }
     }
 
diff --git a/polymer/eduke32/package/sdk/tiles.cfg b/polymer/eduke32/package/sdk/tiles.cfg
index eb5aa4f58..00dfc6323 100644
--- a/polymer/eduke32/package/sdk/tiles.cfg
+++ b/polymer/eduke32/package/sdk/tiles.cfg
@@ -7,7 +7,22 @@ tilegroup "Actors"
 {
 	hotkey "A"
 
-	colors 31 31
+    // NOTE: colors specified here (as well as in the first argument to the DEF
+    // commands '2dcol' and '2dcolidxrange') refer to Mapster32's editorcolor[]
+    // index. They can be viewed with "set showpal 1" assuming that a.m32 has
+    // been loaded.
+    //
+    // The actual color indices will be offset in the range [0 .. 4] when the
+    // mouse hovers near them.
+    //
+    // For example, under the Duke3D palette, one can create a color scheme
+    // similar to earlier Mapster32 builds (non-blocking sprites have an orange
+    // tint, blocking ones are purple) by declaring in a loaded DEF file
+    //  2dcolidxrange 33 33 255
+    // which maps editorcolor[] indices 33 through 255 to the same actual color
+    // indices, and then setting here:
+//    colors 139 231
+    colors 31 31
 
 	tiles
 	{
diff --git a/polymer/eduke32/source/astub.c b/polymer/eduke32/source/astub.c
index 16fa6cc64..c0d5eb8ba 100644
--- a/polymer/eduke32/source/astub.c
+++ b/polymer/eduke32/source/astub.c
@@ -7847,6 +7847,7 @@ static void InitCustomColors(void)
     vgapal16[31*4+1] = 180; // green
     vgapal16[31*4+2] = 240; // red
 
+    // UNUSED?
     vgapal16[39*4+0] = 144;
     vgapal16[39*4+1] = 212;
     vgapal16[39*4+2] = 252;
@@ -7880,10 +7881,12 @@ static void InitCustomColors(void)
     vgapal16[26*4+1] = 96;
     vgapal16[26*4+2] = 96;
 
+    // UNUSED?
     vgapal16[33*4+0] = 0; //60; // blue
     vgapal16[33*4+1] = 0; //120; // green
     vgapal16[33*4+2] = 192; //180; // red
 
+    // UNUSED?
     vgapal16[41*4+0] = 0; //96;
     vgapal16[41*4+1] = 0; //160;
     vgapal16[41*4+2] = 252; //192;