diff --git a/src/FDM/JSBSim/models/propulsion/FGPropeller.cpp b/src/FDM/JSBSim/models/propulsion/FGPropeller.cpp
index 389f69322..841f87c8a 100644
--- a/src/FDM/JSBSim/models/propulsion/FGPropeller.cpp
+++ b/src/FDM/JSBSim/models/propulsion/FGPropeller.cpp
@@ -228,7 +228,15 @@ double FGPropeller::Calculate(double EnginePower)
   // Induced velocity in the propeller disk area. This formula is obtained
   // from momentum theory - see B. W. McCormick, "Aerodynamics, Aeronautics,
   // and Flight Mechanics" 1st edition, eqn. 6.15 (propeller analysis chapter).
-  Vinduced = 0.5 * (-Vel + sqrt(Vel*Vel + 2.0*Thrust/(rho*Area)));
+  // Vinduced = 0.5 * (-Vel + sqrt(Vel*Vel + 2.0*Thrust/(rho*Area)))
+  // Since Thrust and Vel can both be negative we need to adjust this formula
+  // To handle sign (direction) separately from magnitude.
+  double Vel2sum = Vel*abs(Vel) + 2.0*Thrust/(rho*Area);
+
+  if( Vel2sum > 0.0)
+    Vinduced = 0.5 * (-Vel + sqrt(Vel2sum));
+  else
+    Vinduced = 0.5 * (-Vel - sqrt(-Vel2sum));
 
   // P-factor is simulated by a shift of the acting location of the thrust.
   // The shift is a multiple of the angle between the propeller shaft axis
diff --git a/src/Input/FGMacOSXEventInput.cxx b/src/Input/FGMacOSXEventInput.cxx
index 28c3094cc..5c0fe4505 100644
--- a/src/Input/FGMacOSXEventInput.cxx
+++ b/src/Input/FGMacOSXEventInput.cxx
@@ -39,10 +39,12 @@ using std::string;
       value; })
 
 #define GetHIDElementStringValue(element, key) ({ \
-      const char *buf = ""; \
+      const char *ref = ""; \
+      const char *buf = ref; \
       CFStringRef refType = (CFStringRef)CFDictionaryGetValue(element, CFSTR(key)); \
       if (refType) { \
         buf = CFStringGetCStringPtr(refType, CFStringGetSystemEncoding());  \
+        if (!buf) buf = ref; \
        } \
       buf; })
 
@@ -126,19 +128,19 @@ struct HIDTypes HID_USAGE_TABLE[] = {
   {GD_USAGE(kHIDUsage_GD_Vbrz), kHIDUsageAxis, "z-rel-vector"},
   {GD_USAGE(kHIDUsage_GD_Vno),  kHIDUsageAxis, "no-vector"},
 
-  {GD_USAGE(kHIDUsage_GD_SystemPowerDown), kHIDUsageOSC, "button-system-power-down"},
-  {GD_USAGE(kHIDUsage_GD_SystemSleep), kHIDUsageOSC, "button-system-sleep"},
-  {GD_USAGE(kHIDUsage_GD_SystemWakeUp), kHIDUsageOSC, "button-system-wake-up"},
-  {GD_USAGE(kHIDUsage_GD_SystemContextMenu), kHIDUsageOSC, "button-system-context-menu"},
-  {GD_USAGE(kHIDUsage_GD_SystemMainMenu), kHIDUsageOSC, "button-system-main-menu"},
-  {GD_USAGE(kHIDUsage_GD_SystemAppMenu), kHIDUsageOSC, "button-system-app-menu"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuHelp), kHIDUsageOSC, "button-system-menu-help"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuExit), kHIDUsageOSC, "button-system-menu-exit"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenu), kHIDUsageOSC, "button-system-menu"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuRight), kHIDUsageRTC, "button-system-menu-right"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuLeft), kHIDUsageRTC, "button-system-menu-left"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuUp), kHIDUsageRTC, "button-system-menu-up"},
-  {GD_USAGE(kHIDUsage_GD_SystemMenuDown), kHIDUsageRTC, "button-system-menu-down"},
+  {GD_USAGE(kHIDUsage_GD_SystemPowerDown), kHIDUsageOSC, "system-power-down"},
+  {GD_USAGE(kHIDUsage_GD_SystemSleep), kHIDUsageOSC, "system-sleep"},
+  {GD_USAGE(kHIDUsage_GD_SystemWakeUp), kHIDUsageOSC, "system-wake-up"},
+  {GD_USAGE(kHIDUsage_GD_SystemContextMenu), kHIDUsageOSC, "system-context-menu"},
+  {GD_USAGE(kHIDUsage_GD_SystemMainMenu), kHIDUsageOSC, "system-main-menu"},
+  {GD_USAGE(kHIDUsage_GD_SystemAppMenu), kHIDUsageOSC, "system-app-menu"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuHelp), kHIDUsageOSC, "system-menu-help"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuExit), kHIDUsageOSC, "system-menu-exit"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenu), kHIDUsageOSC, "system-menu"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuRight), kHIDUsageRTC, "system-menu-right"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuLeft), kHIDUsageRTC, "system-menu-left"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuUp), kHIDUsageRTC, "system-menu-up"},
+  {GD_USAGE(kHIDUsage_GD_SystemMenuDown), kHIDUsageRTC, "system-menu-down"},
   {GD_USAGE(kHIDUsage_GD_DPadUp), kHIDUsageOOC, "dpad-up"},
   {GD_USAGE(kHIDUsage_GD_DPadDown), kHIDUsageOOC, "dpad-down"},
   {GD_USAGE(kHIDUsage_GD_DPadRight), kHIDUsageOOC, "dpad-right"},
@@ -151,7 +153,7 @@ struct HIDTypes HID_USAGE_TABLE[] = {
   {GAME_USAGE(kHIDUsage_Game_MoveForwardOrBackward), kHIDUsageAxis, "y-move"},
   {GAME_USAGE(kHIDUsage_Game_MoveUpOrDown), kHIDUsageAxis, "z-move"},
   {GAME_USAGE(kHIDUsage_Game_LeanRightOrLeft), kHIDUsageAxis, "x-lean"},
-  {GAME_USAGE(kHIDUsage_Game_LeanForwardOrBackward), kHIDUsageAxis, "z-lean"},
+  {GAME_USAGE(kHIDUsage_Game_LeanForwardOrBackward), kHIDUsageAxis, "y-lean"},
 
   // General Control Devices Page
   {GDC_USAGE(0x20), kHIDUsageDV, "battery-strength"},
@@ -382,7 +384,7 @@ ButtonElement::ButtonElement(CFDictionaryRef element, long page, long usage) :
 {
   if (name == "") {
     stringstream ss;
-    ss << (page == kHIDPage_KeyboardOrKeypad ? "keyboard-" : "button-") << usage;
+    ss << (page == kHIDPage_KeyboardOrKeypad ? "keyboard-" : "button-") << usage - 1;
     ss >> name;
   }
 }
@@ -498,7 +500,7 @@ void HIDElementFactory::parseElement(CFDictionaryRef element, FGMacOSXInputDevic
     // FIXME: Any other elegant way for counting the same usage on a device?
     // This is mainly needed for feature / hat elements to avoid assigning the sane event name.
     elementCount[inputDevice][USAGE_KEY(page, usage)] += 1;
-    
+
     switch (usageType) {
       case kHIDUsageAxis:
 	  inputDevice->addElement(new AxisElement(element, page, usage));
@@ -519,7 +521,7 @@ void HIDElementFactory::parseElement(CFDictionaryRef element, FGMacOSXInputDevic
           break;
           
       default:
-        if (page == kHIDPage_Button || type == kIOHIDElementTypeInput_Button && usage > 0) {
+        if ((page == kHIDPage_Button || type == kIOHIDElementTypeInput_Button) && usage > 0) {
         // FIXME: most of KeyboardOrKeypad elements should be treated as Selector type, not as Button...
 	  inputDevice->addElement(new ButtonElement(element, page, usage));
         } else if (page == kHIDPage_LEDs && usage > 0) {
diff --git a/src/Input/fgjs.cxx b/src/Input/fgjs.cxx
index 9a873ed51..9c4e66487 100644
--- a/src/Input/fgjs.cxx
+++ b/src/Input/fgjs.cxx
@@ -58,6 +58,10 @@ using std::string;
 
 #include "jsinput.h"
 
+#ifdef __APPLE__
+#  include <CoreFoundation/CoreFoundation.h>
+#endif
+
 using simgear::PropertyList;
 
 bool confirmAnswer() {
@@ -342,25 +346,23 @@ string getFGRoot ( int argc, char **argv ) {
         root = "../data";
 #elif defined( _WIN32 )
         root = "..\\data";
-#elif defined(OSX_BUNDLE)
-        /* the following code looks for the base package directly inside
-            the application bundle. This can be changed fairly easily by
-            fiddling with the code below. And yes, I know it's ugly and verbose.
+#elif defined(__APPLE__) 
+        /*
+        The following code looks for the base package inside the application 
+        bundle, in the standard Contents/Resources location. 
         */
-        CFBundleRef appBundle = CFBundleGetMainBundle();
-        CFURLRef appUrl = CFBundleCopyBundleURL(appBundle);
-        CFRelease(appBundle);
 
-        // look for a 'data' subdir directly inside the bundle : is there
-        // a better place? maybe in Resources? I don't know ...
-        CFURLRef dataDir = CFURLCreateCopyAppendingPathComponent(NULL, appUrl, CFSTR("data"), true);
+        CFURLRef resourcesUrl = CFBundleCopyResourcesDirectoryURL(CFBundleGetMainBundle());
+
+        // look for a 'data' subdir
+        CFURLRef dataDir = CFURLCreateCopyAppendingPathComponent(NULL, resourcesUrl, CFSTR("data"), true);
 
         // now convert down to a path, and the a c-string
         CFStringRef path = CFURLCopyFileSystemPath(dataDir, kCFURLPOSIXPathStyle);
         root = CFStringGetCStringPtr(path, CFStringGetSystemEncoding());
 
         // tidy up.
-        CFRelease(appBundle);
+        CFRelease(resourcesUrl);
         CFRelease(dataDir);
         CFRelease(path);
 #else