diff --git a/fsl/utils/dialog.py b/fsl/utils/dialog.py
index cc85e6a19069c3a2b9ca32f82871a21e34864c0a..a6e277f63e087deee87f575eb934b83eb4923f26 100644
--- a/fsl/utils/dialog.py
+++ b/fsl/utils/dialog.py
@@ -22,6 +22,8 @@ import threading
 
 import wx
 
+from fsl.utils.platform import platform as fslplatform
+
 
 class SimpleMessageDialog(wx.Dialog):
     """A simple, no-frills :class:`wx.Dialog` for displaying a message. The
@@ -637,16 +639,14 @@ class FSLDirDialog(wx.Dialog):
 
         self.__icon.SetBitmap(bmp)
         self.__message.SetLabel(
-            'The $FSLDIR environment variable '
-            'is not set - {} may not behave '
-            'correctly.'.format(toolName))
+            'The $FSLDIR environment variable is not set - {} '
+            'may not behave correctly.'.format(toolName))
         self.__locate .SetLabel('Locate $FSLDIR')
         self.__skip   .SetLabel('Skip')
 
         self.__skip  .Bind(wx.EVT_BUTTON, self.__onSkip)
         self.__locate.Bind(wx.EVT_BUTTON, self.__onLocate)
 
-
         self.__mainSizer    = wx.BoxSizer(wx.HORIZONTAL)
         self.__contentSizer = wx.BoxSizer(wx.VERTICAL)
         self.__buttonSizer  = wx.BoxSizer(wx.HORIZONTAL)
@@ -671,8 +671,9 @@ class FSLDirDialog(wx.Dialog):
         self.__message.Wrap(self.GetSize().GetWidth())
 
         self.SetSizer(self.__mainSizer)
-        self.Layout()
-        self.Fit()
+        self.__mainSizer.Layout()
+        self.__mainSizer.Fit(self)
+
         self.CentreOnParent()
 
         
diff --git a/fsl/utils/platform.py b/fsl/utils/platform.py
index c3d6ca7a0b687932a464d07533b3612653bc2a4b..b35c5a1a76226160e75bff25b105ed10e2651410 100644
--- a/fsl/utils/platform.py
+++ b/fsl/utils/platform.py
@@ -70,7 +70,7 @@ class Platform(notifier.Notifier):
 
        fsldir
        haveGui
-       wxBuild
+       wxPlatform
        wxFlavour
        glVersion
        glRenderer
@@ -79,7 +79,14 @@ class Platform(notifier.Notifier):
     
     def __init__(self):
         """Create a ``Platform`` instance. """
-        
+
+        # For things which 'from fsl.utils.platform import platform',
+        # these identifiers are available on the platform instance
+        self.WX_PYTHON     = WX_PYTHON
+        self.WX_PHOENIX    = WX_PHOENIX
+        self.WX_MAC_COCOA  = WX_MAC_COCOA
+        self.WX_MAC_CARBON = WX_MAC_CARBON
+        self.WX_GTK        = WX_GTK
 
         self.__fsldir     = os.environ.get('FSLDIR', None)
         self.__haveGui    = False
@@ -108,16 +115,16 @@ class Platform(notifier.Notifier):
             if isPhoenix: self.__wxFlavour = WX_PHOENIX
             else:         self.__wxFlavour = WX_PYTHON
 
-            if   any(['cocoa'  in p for p in pi]): build = WX_MAC_COCOA
-            elif any(['carbon' in p for p in pi]): build = WX_MAC_CARBON
-            elif any(['gtk'    in p for p in pi]): build = WX_GTK
-            else:                                  build = None
+            if   any(['cocoa'  in p for p in pi]): platform = WX_MAC_COCOA
+            elif any(['carbon' in p for p in pi]): platform = WX_MAC_CARBON
+            elif any(['gtk'    in p for p in pi]): platform = WX_GTK
+            else:                                  platform = None
 
-            self.__build = build
+            self.__wxPlatform = platform
 
-            if self.__build is None:
-                log.warning('Could not determine wx build from '
-                            'platform information: {}'.format(pi))
+            if self.__wxPlatform is None:
+                log.warning('Could not determine wx platform from '
+                            'information: {}'.format(pi))
 
 
     @property
@@ -127,11 +134,11 @@ class Platform(notifier.Notifier):
 
     
     @property
-    def wxBuild(self):
+    def wxPlatform(self):
         """One of :data:`WX_MAC_COCOA`, :data:`WX_MAC_CARBON`, or
-        :data:`WX_GTK`, indicating the wx build.
+        :data:`WX_GTK`, indicating the wx platform.
         """
-        return self.__wxBuild
+        return self.__wxPlatform
 
     
     @property