diff --git a/cat/dat/GUI.cfg b/cat/dat/GUI.cfg
index 35d79c153b76bf83588635acfc5b5f31a8cdfbfb..91adfa92779aa18b2356f3b778ee44edc0757e21 100644
--- a/cat/dat/GUI.cfg
+++ b/cat/dat/GUI.cfg
@@ -9,21 +9,21 @@ Array:GQ
 Plot:ISOREC
 Palette:AUTO
 Title:Vorticity
-Geometry: 1000 1000    1    0
+Geometry: 1000 1000    1    1
 
 [Window 01]
-Array:GXM
-Plot:LINE
+Array:C4
+Plot:ISOAMP
 Palette:AUTO
-Title:GXM
-Geometry:  853  367  853   -1
+Title:Vorticity
+Geometry:  540  1000  1050   1
 
 [Window 02]
 Array:QC
 Plot:ISOAMP
 Palette:AMPLI
 Title:C4
-Geometry:  853  367 1706   -1
+Inactive:  853  367 1706   -1
 
 [Window 03]
 Array:GP
diff --git a/cat/dat/GUI_Amp.cfg b/cat/dat/GUI_Amp.cfg
new file mode 100644
index 0000000000000000000000000000000000000000..91adfa92779aa18b2356f3b778ee44edc0757e21
--- /dev/null
+++ b/cat/dat/GUI_Amp.cfg
@@ -0,0 +1,139 @@
+Hamburg GUI Config File Version 16
+Screen: 2560x1418
+
+WinRows = 3
+WinCols = 3
+
+[Window 00]
+Array:GQ
+Plot:ISOREC
+Palette:AUTO
+Title:Vorticity
+Geometry: 1000 1000    1    1
+
+[Window 01]
+Array:C4
+Plot:ISOAMP
+Palette:AUTO
+Title:Vorticity
+Geometry:  540  1000  1050   1
+
+[Window 02]
+Array:QC
+Plot:ISOAMP
+Palette:AMPLI
+Title:C4
+Inactive:  853  367 1706   -1
+
+[Window 03]
+Array:GP
+Plot:MAPHOR
+Projection:POLAR
+Rotation factor:0
+Palette:P
+Title:Surface Pressure [hPa]
+Inactive:  853  367    0  389
+
+[Window 04]
+Array:GU
+Plot:MAPTRA
+Projection:AZIMUTHAL
+Rotation factor:0
+Palette:U
+Title:Tracer Level 3
+Inactive:  853  367  853  389
+
+[Window 05]
+Array:GV
+Plot:ISOLON
+Palette:U
+Title:Meridional Wind [m/s] Latitude 42N
+Inactive:  853  367 1706  389
+
+[Window 06]
+Array:GP
+Plot:ISOHOV
+Palette:P
+Title:Ps Hovmoeller Latitude 42N
+Inactive:  853  367    0  779
+
+[Window 07]
+Array:SCALAR
+Plot:ISOTS
+Palette:AUTO
+Title:Timeseries
+Inactive:  853  367  853  779
+
+[Window 08]
+Array:SCALAR
+Plot:ISOTAB
+Palette:AUTO
+Title:Tables
+Inactive:  853  367 1706  779
+
+[Control Window]
+Geometry:  920  122  820 1171
+
+# Scalar attributes for timeseries and table window
+
+[Scalar 00]
+Name:T
+Sub:
+Unit:C
+Scale:
+
+[Scalar 01]
+Name:RMS Div
+Sub:
+Unit:1/s
+Scale:-6
+
+[Scalar 02]
+Name:PE+KE
+Sub:
+Unit:m2/s2
+Scale:
+
+[Scalar 03]
+Name:RMS Ps
+Sub:
+Unit:hPa
+Scale:
+
+[Scalar 04]
+Name:Vort
+Sub:
+Unit:1/s
+Scale:
+
+# Parameter attributes for change menu
+
+[Parameter 00]
+ParName:NGUI
+ParInc:    1.0000
+ParMin:    1.0000
+ParMax: 1000.0000
+
+[Parameter 01]
+ParName:QMAX
+ParInc:    1.0000
+ParMin:    0.0000
+ParMax: 1000.0000
+
+[Parameter 02]
+ParName:DTNS
+ParInc:    5.0000
+ParMin:  -95.0000
+ParMax:  100.0000
+
+[Parameter 03]
+ParName:NSYNC
+ParInc:    1.0000
+ParMin:    0.0000
+ParMax:    1.0000
+
+[Parameter 04]
+ParName:EPSYNC
+ParInc:    1.0000
+ParMin:    0.0000
+ParMax:  100.0000
diff --git a/cat/src/guix11.c b/cat/src/guix11.c
index dc5af3e74bc8bbe510a1d7e6fe04e2fc4f33a06c..7f0de9d1497ed2c6bf7913f5220f34689eb4fd9b 100644
--- a/cat/src/guix11.c
+++ b/cat/src/guix11.c
@@ -3111,11 +3111,11 @@ void SH_Amplitudes(int w)
 }
 
 
-/* ========== */
-/* Amplitudes */
-/* ========== */
+/* ============= */
+/* FC_Amplitudes */
+/* ============= */
 
-void Amplitudes(int w)
+void FC_Amplitudes(int w)
 {
    int i,j,m,n;
    int x,y;
@@ -3155,14 +3155,17 @@ void Amplitudes(int w)
 
    dx = WinXSize / (DimX+1);
    dy = WinYSize / (DimY+1);
+   if (dx < dy) dy = dx;
+   else         dx = dy;
    r  = (dx+dx+dy+dy) / 6;
    XSetForeground(display,gc,BlackPix);
-   for (m=0,i=0 ; m < DimX ; ++m)
+   i = 0;
+   for (n=0 ; n < DimY ; ++n)
    {
-      y = FixFontHeight + 4 + m * dx;
-      for (n=0 ; n < DimY ; ++n)
+      y = FixFontHeight + 4 + n * dy;
+      for (m=0 ; m < DimX ; ++m)
       {
-         x = dx/2 + n * dx;
+         x = dx/2 + m * dx;
          XSetForeground(display,gc,Aco[w][i++].pixel);
          XFillArc(display,pix,gc,x,y,r,r,0,360*64);
       }
@@ -4206,7 +4209,7 @@ void iso(int w,int PicType,REAL *field,int dimx,int dimy,int dimz,int pal)
    char Text[128];
 
    int i,j,k,len,lens,xp,yp,status,x;
-   int y,dx,r,width,height;
+   int y,dx,dy,r,width,height;
    INTXU border,depth;
    REAL f,o,ra,rb;
    int CapLines;
@@ -4556,7 +4559,10 @@ void iso(int w,int PicType,REAL *field,int dimx,int dimy,int dimz,int pal)
 
    if (SizeChanged && PicType == ISOAMP)
    {
-      dx = WinXSize / DimX;
+      dx = WinXSize / (DimX+1);
+      dy = WinYSize / (DimY+1);
+      if (dx < dy) dy = dx;
+      else         dx = dy;
       XSetForeground(display,gc,BlackPix);
       XFillRectangle(display,pix,gc,0,0,WinXSize,WinYSize);
 
@@ -4580,7 +4586,7 @@ void iso(int w,int PicType,REAL *field,int dimx,int dimy,int dimz,int pal)
          width  = XTextWidth(FixFont,Text,len);
          height = FixFont->ascent + FixFont->descent;
          xp     = WinXSize - width - 2;
-         yp     = 2 * FixFontHeight + i * dx;
+         yp     = 2 * FixFontHeight + i * dy;
          if (yp+FixFont->descent > InYSize) break;
          XDrawImageString(display,pix,gc,xp,yp,Text,len);
       }
@@ -4859,7 +4865,7 @@ void iso(int w,int PicType,REAL *field,int dimx,int dimy,int dimz,int pal)
 
    if (PicType == ISOAMP)
    {
-      Amplitudes(w);
+      FC_Amplitudes(w);
    }
 
    // line plot