diff -u CalculiX/cgx_2.10/src.orig/Makefile CalculiX/cgx_2.10/src/Makefile
--- CalculiX/cgx_2.10/src.orig/Makefile	2016-03-30 18:51:05.000000000 -0500
+++ CalculiX/cgx_2.10/src/Makefile	2016-03-30 19:57:16.000000000 -0500
@@ -1,4 +1,4 @@
-CFLAGS = -O3 -Wall \
+CFLAGS = \
   -I./ \
   -I/usr/include \
   -I/usr/include/GL \
@@ -7,9 +7,8 @@
   -I/usr/X11/include 
 
 LFLAGS = \
-  -L/usr/lib64 -lGL -lGLU \
-  -L/usr/X11R6/lib64 -lX11 -lXi -lXmu -lXext -lXt -lSM -lICE \
-  -lm -lpthread -lrt
+  -L/usr/lib -lGL -lGLU \
+  -L/usr/X11R6/lib -lX11 -lXi -lXmu -lXext -lXt -lSM -lICE 
 
 
 # on 32bit systems change lib64 to lib
@@ -66,7 +65,7 @@
 OUTIL = $(SUTIL:.c=.o)
 
 cgx: $(OLIB) $(OUTIL) $(OULIB)
-	g++  $(OULIB)  $(OLIB) $(OUTIL)  $(CFLAGS) $(LFLAGS) -o  $@
+	$(CC)  $(OULIB)  $(OLIB) $(OUTIL)  $(CFLAGS) $(LFLAGS) -o  $@
 
 
 
diff -u CalculiX/cgx_2.10/src.orig/cgx.h CalculiX/cgx_2.10/src/cgx.h
--- CalculiX/cgx_2.10/src.orig/cgx.h	2016-03-30 18:51:05.000000000 -0500
+++ CalculiX/cgx_2.10/src/cgx.h	2016-04-01 18:24:02.000000000 -0500
@@ -79,12 +79,12 @@
                              "/yaprod/cae/application/CalculiX/doc/ccx_2.10/ccx.html"}
   #endif
 #elif defined AFLIB
-  #define     HELPFILE        {"/usr/local/CalculiX/cgx_2.10/doc/cgx/cgx.html",\
-    "/usr/local/CalculiX/ccx_2.10/doc/ccx/ccx.html",\
-    "/usr/local/CalculiX/cgx_2.10/doc/aflib/aflib.pdf"}
+  #define     HELPFILE        {"@@PREFIX@@/libexec/CalculiX/cgx_2.10/doc/cgx/cgx.html",\
+    "@@PREFIX@@/libexec/CalculiX/ccx_2.10/doc/ccx/ccx.html",\
+    "@@PREFIX@@/libexec/CalculiX/cgx_2.10/doc/aflib/aflib.pdf"}
 #else
-  #define     HELPFILE        {"/usr/local/CalculiX/cgx_2.10/doc/cgx/cgx.html",\
-    "/usr/local/CalculiX/ccx_2.10/doc/ccx/ccx.html"}
+  #define     HELPFILE        {"@@PREFIX@@/libexec/CalculiX/cgx_2.10/doc/cgx/cgx.html",\
+    "@@PREFIX@@/libexec/CalculiX/ccx_2.10/doc/ccx/ccx.html"}
 #endif
 
 /* html browser, change if necessary */
@@ -95,9 +95,9 @@
 #else
 /* #define     BROWSER         {"netscape"} */
 /*   #define     BROWSER         {"mozilla"} */
-  #define     BROWSER         {"firefox"}
+  #define     BROWSER         {"openbrowser"}
 /* #define     PSVIEWER         {"ghostview"} */
-  #define     PSVIEWER         {"gv"}
+  #define     PSVIEWER         {"open"}
 #endif
 
 /* more parameters, better do not change them! */