diff --git a/polymer/eduke32/build/include/build.h b/polymer/eduke32/build/include/build.h
index 00d0630bc..6b6208313 100644
--- a/polymer/eduke32/build/include/build.h
+++ b/polymer/eduke32/build/include/build.h
@@ -611,6 +611,7 @@ typedef struct {
 
 EXTERN int32_t guniqhudid;
 EXTERN int32_t spritesortcnt;
+extern int32_t g_loadedMapVersion;
 
 #if !defined DEBUG_MAIN_ARRAYS
 EXTERN spriteext_t *spriteext;
diff --git a/polymer/eduke32/build/src/build.c b/polymer/eduke32/build/src/build.c
index 39bb3ebe3..bb7245dc5 100644
--- a/polymer/eduke32/build/src/build.c
+++ b/polymer/eduke32/build/src/build.c
@@ -100,7 +100,6 @@ int32_t zoom = 768, gettilezoom = 1;
 int32_t lastpm16time = 0;
 
 extern int32_t mapversion;
-extern int32_t g_loadedMapVersion;
 
 int16_t highlight[MAXWALLS+MAXSPRITES];
 int16_t highlightsector[MAXSECTORS], highlightsectorcnt = -1;
diff --git a/polymer/eduke32/build/src/engine.c b/polymer/eduke32/build/src/engine.c
index dc3d94fd8..27644e1eb 100644
--- a/polymer/eduke32/build/src/engine.c
+++ b/polymer/eduke32/build/src/engine.c
@@ -84,13 +84,13 @@ int32_t g_loadedMapVersion = -1;  // -1: none (e.g. started new)
 
 static int32_t get_mapversion(void);
 
-// Handle nonpow2-ysize walls walls the old way?
+// Handle nonpow2-ysize walls the old way?
 static inline int32_t oldnonpow2(void)
 {
 #if !defined CLASSIC_NONPOW2_YSIZE_WALLS
     return 1;
 #else
-    return (mapversion < 10);
+    return (g_loadedMapVersion < 10);
 #endif
 }
 
diff --git a/polymer/eduke32/build/src/polymer.c b/polymer/eduke32/build/src/polymer.c
index 7306a093c..fccbc3085 100644
--- a/polymer/eduke32/build/src/polymer.c
+++ b/polymer/eduke32/build/src/polymer.c
@@ -2820,23 +2820,29 @@ static int32_t      polymer_initwall(int16_t wallnum)
 
 static float calc_ypancoef(char curypanning, int16_t curpicnum, int32_t dopancor)
 {
-    float ypancoef = (float)(pow2long[picsiz[curpicnum] >> 4]);
-
-    if (ypancoef < tilesizy[curpicnum])
-        ypancoef *= 2;
-
-    if (dopancor)
+#ifdef NEW_MAP_FORMAT
+    if (g_loadedMapVersion >= 10)
+        return curypanning / 256.0f;
+#endif
     {
-        int32_t yoffs;
+        float ypancoef = (float)(pow2long[picsiz[curpicnum] >> 4]);
 
-        ftol((ypancoef - tilesizy[curpicnum]) * (255.0f / ypancoef), &yoffs);
-        if (curypanning > 256 - yoffs)
-            curypanning -= yoffs;
+        if (ypancoef < tilesizy[curpicnum])
+            ypancoef *= 2;
+
+        if (dopancor)
+        {
+            int32_t yoffs;
+
+            ftol((ypancoef - tilesizy[curpicnum]) * (255.0f / ypancoef), &yoffs);
+            if (curypanning > 256 - yoffs)
+                curypanning -= yoffs;
+        }
+
+        ypancoef *= (float)curypanning / (256.0f * (float)tilesizy[curpicnum]);
+
+        return ypancoef;
     }
-
-    ypancoef *= (float)curypanning / (256.0f * (float)tilesizy[curpicnum]);
-
-    return ypancoef;
 }
 
 static void         polymer_updatewall(int16_t wallnum)
diff --git a/polymer/eduke32/build/src/polymost.c b/polymer/eduke32/build/src/polymost.c
index 83a4cd3aa..e190d2400 100644
--- a/polymer/eduke32/build/src/polymost.c
+++ b/polymer/eduke32/build/src/polymost.c
@@ -2249,31 +2249,27 @@ static void calc_ypanning(int32_t refposz, double ryp0, double ryp1,
 {
     int32_t i;
     double t0, t1, t, fy;
-    int32_t yoffs;  // for panning "correction"
 
     t0 = ((float)(refposz-globalposz))*ryp0 + ghoriz;
     t1 = ((float)(refposz-globalposz))*ryp1 + ghoriz;
     t = ((gdx*x0 + gdo) * (float)yrepeat) / ((x1-x0) * ryp0 * 2048.f);
     i = (1<<(picsiz[globalpicnum]>>4)); if (i < tilesizy[globalpicnum]) i <<= 1;
 
+#ifdef NEW_MAP_FORMAT
+    if (g_loadedMapVersion >= 10)
+        i = tilesizy[globalpicnum];
+    else
+#endif
     if (dopancor)
     {
+        // Carry out panning "correction" to make it look like classic in some
+        // cases, but failing in the general case.
+        int32_t yoffs;
+
         ftol((i-tilesizy[globalpicnum])*(255.f/i), &yoffs);
 
-        if (ypan>256-yoffs)
-        {
-            ypan-=yoffs;
-        }
-    }
-    else
-    {
-        // (1)
-        // not hacked yet
-
-        // (2)
-        // Still need a hack, depending on the wall(height,ypanning,yrepeat,tilesizy)
-        // it should do "ypan-=yoffs" or "ypan+=yoffs" or [nothing].
-        // Example: the film projector in the E1L1.map needs "ypan-=yoffs"
+        if (ypan > 256-yoffs)
+            ypan -= yoffs;
     }
 
     fy = (float)ypan * ((float)i) / 256.0;