Configuring custom keys on bluetooth keyboard
Download and install KeyRemap4MacBook.
Open EventViewer:

open /Applications/KeyRemap4MacBook.app/Contents/Applications/EventViewer.app

Press the key that you wish to customise and note the KeyCode:::


Create a private.xml like this:

&lt;?xml version="1.0"?&gt;
&lt;root&gt;
  &lt;item&gt;
    &lt;name&gt;Modifier Remapping&lt;/name&gt;
    &lt;identifier&gt;modremap&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::CONTROL_L, KeyCode::COMMAND_L&lt;/autogen&gt;
  &lt;/item&gt;
&lt;/root&gt;


Replace KeyCode::CONTROL_L with the key that you wish to change and  KeyCode::COMMAND_L with the key that you wish to replace it with.