diff --git a/cameo/templates/mkmk-simple b/cameo/templates/mkmk-simple
index 682bc86..9ac3175 100755
--- a/cameo/templates/mkmk-simple
+++ b/cameo/templates/mkmk-simple
@@ -85,8 +85,8 @@ EOF
     yi=`expr $yi + 1`
 done
 
-gp2rml $CLEARANCE 0.5 0.5 mill.gp >mill.rml
-gp2rml $CLEARANCE 0.1 0.5 drill.gp >drill.rml
+gp2rml $CLEARANCE 0.5 0.5 mill.gp >mill.rml || exit
+gp2rml $CLEARANCE 0.1 0.5 drill.gp >drill.rml || exit
 
 
 cat <<EOF >Makefile.mkmk