Explicitly set the preferred song in SSM's ctor, instead of handling it in

the music wheel.  This way, we can re-set the preferred song at any time
and have it take effect when we get back to the wheel; previously, if
we'd already played a song, m_pCurSong would override it.

stepmania/src/MusicWheel.cpp

@@ -258,12 +258,8 @@ bool MusicWheel::SelectSongOrCourse()
 {
 	if( GAMESTATE->m_pCurSong && SelectSong( GAMESTATE->m_pCurSong ) )
 		return true;
-	if( GAMESTATE->m_pPreferredSong && SelectSong( GAMESTATE->m_pPreferredSong ) )
-		return true;
 	if( GAMESTATE->m_pCurCourse && SelectCourse( GAMESTATE->m_pCurCourse ) )
 		return true;
-	if( GAMESTATE->m_pPreferredCourse && SelectCourse( GAMESTATE->m_pPreferredCourse ) )
-		return true;
 
 	// Select the first selectable song based on the sort order...
 	vector<WheelItemData> &wiWheelItems = m_WheelItemDatas[m_SortOrder];

stepmania/src/ScreenSelectMusic.cpp

@@ -71,6 +71,15 @@ ScreenSelectMusic::ScreenSelectMusic( CString sClassName ) : ScreenWithMenuEleme
 	/* Finish any previous stage.  It's OK to call this when we havn't played a stage yet. 
 	 * Do this before anything that might look at GAMESTATE->m_iCurrentStageIndex. */
 	GAMESTATE->FinishStage();
+
+	/* If we have a preferred song, let it override the active song.  That way, you
+	 * can set PreferredSong at any time (eg. during initial menus or evaluation) to
+	 * select the default song for the next play, without interfering with things
+	 * that still need pCurSong. */
+	if( GAMESTATE->m_pPreferredSong )
+		GAMESTATE->m_pCurSong.Set( GAMESTATE->m_pPreferredSong );
+	if( GAMESTATE->m_pPreferredCourse )
+		GAMESTATE->m_pCurCourse = GAMESTATE->m_pPreferredCourse;
 }