diff --git a/materials.xml b/materials.xml
index 5239fe2d2..8e41fbfd9 100644
--- a/materials.xml
+++ b/materials.xml
@@ -2935,7 +2935,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.92157</g>
    <b>0.76471</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -2945,7 +2945,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.92157</g>
    <b>0.76471</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -2955,7 +2955,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.92157</g>
    <b>0.76471</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -2985,7 +2985,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.92157</g>
    <b>0.76471</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -2995,7 +2995,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.92157</g>
    <b>0.76471</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -3005,7 +3005,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.84314</g>
    <b>0.078431</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -3035,7 +3035,7 @@ Shared parameters for various materials.
    <r>0.92157</r>
    <g>0.35294</g>
    <b>0.35294</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
@@ -3065,7 +3065,7 @@ Shared parameters for various materials.
    <r>0.078431</r>
    <g>0.92157</g>
    <b>0.078431</b>
-   <a>1</a>
+   <a>1.0</a>
   </emissive>
  </material>
 
diff --git a/preferences.xml b/preferences.xml
index 38dc73a39..a2c22b809 100644
--- a/preferences.xml
+++ b/preferences.xml
@@ -58,6 +58,7 @@ Started September 2000 by David Megginson, david@megginson.com
    <debug type="bool">false</debug>
    <realism>5</realism>
    <filtering>8</filtering>
+   <multithreading-mode>AutomaticSelection</multithreading-mode>
    <static-lod>
     <detailed userarchive="y">1500</detailed>
     <rough userarchive="y">9000</rough>