diff --git a/nif.xml b/nif.xml
index 34f9bd097426058f5232e46dfcb0a644b7270505..6f8c739fe0e9383c9c1a9cd22749e6f5e6ebc9aa 100644
--- a/nif.xml
+++ b/nif.xml
@@ -1643,15 +1643,28 @@
         <add name="Prop Rec Velocity" type="float" default="0">Unknown</add>
         <add name="Const Rec Velocity" type="float" default="0">Unknown</add>
 		<add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
+        <add name="Min Force" type="float" default="-1000000.0">Minimum motor force</add>
+        <add name="Max Force" type="float" default="1000000.0">Maximum motor force</add>
+        <add name="Tau" type="float" default="0">Relative stiffness</add>
+        <add name="Damping" type="float" default="0">Motor damping value</add>
+        <add name="Proportional Recovery Velocity" type="float" default="0">A factor of the current error to calculate the recovery velocity</add>
+        <add name="Constant Recovery Velocity" type="float" default="0">A constant velocity which is used to recover from errors</add>
+        <add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
     </compound>
 	
 	<compound name="bhkVelocityConstraintMotorDescriptor">
         <add name="Min Force" type="float" default="0">Unknown</add>
         <add name="Max Force" type="float" default="0">Unknown</add>
         <add name="Tau" type="float" default="0">Unknown</add>
+    <compound name="bhkVelocityConstraintMotorDescriptor">
+        <add name="Min Force" type="float" default="-1000000.0">Minimum motor force</add>
+        <add name="Max Force" type="float" default="1000000.0">Maximum motor force</add>
+        <add name="Tau" type="float" default="0">Relative stiffness</add>
         <add name="Target Velocity" type="float" default="0">Unknown</add>
 		<add name="Use Velocity Target" type="bool" default="0">Unknown</add>
 		<add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
+        <add name="Use Velocity Target" type="bool" default="0">Unknown</add>
+        <add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
     </compound>
 	
 	<compound name="bhkSpringDamperConstraintMotorDescriptor">
@@ -1660,6 +1673,12 @@
         <add name="Spring Constant" type="float" default="0">Unknown</add>
         <add name="Spring Damping" type="float" default="0">Unknown</add>		
 		<add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
+    <compound name="bhkSpringDamperConstraintMotorDescriptor">
+        <add name="Min Force" type="float" default="-1000000.0">Minimum motor force</add>
+        <add name="Max Force" type="float" default="1000000.0">Maximum motor force</add>
+        <add name="Spring Constant" type="float" default="0">The spring constant in Nsec/m</add>
+        <add name="Spring Damping" type="float" default="0">The spring damping in Nsec/m</add>       
+        <add name="Motor Enabled" type="bool" default="0">Is Motor enabled</add>
     </compound>
 
     <compound name="MotorDescriptor">
@@ -1667,6 +1686,10 @@
     <add name="Position Motor" type="bhkPositionConstraintMotorDescriptor" cond="Type == 1">Unknown</add>
 	<add name="Velocity Motor" type="bhkVelocityConstraintMotorDescriptor" cond="Type == 2">Unknown</add>
 	<add name="Spring Damper Motor" type="bhkSpringDamperConstraintMotorDescriptor" cond="Type == 3">Unknown</add>
+        <add name="Type" type="byte" default="0">Unknown</add>
+        <add name="Position Motor" type="bhkPositionConstraintMotorDescriptor" cond="Type == 1">Unknown</add>
+        <add name="Velocity Motor" type="bhkVelocityConstraintMotorDescriptor" cond="Type == 2">Unknown</add>
+        <add name="Spring Damper Motor" type="bhkSpringDamperConstraintMotorDescriptor" cond="Type == 3">Unknown</add>
     </compound> 
 
     <compound name="RagdollDescriptor">