Bugfix #5.

Playing of several sequences are improved and close.
is supported without crashing the playuver

source/app/SubWindowHandle.h

@@ -72,6 +72,11 @@ public:
   Int playEvent();
   Void stop();
 
+  Bool isPlaying()
+  {
+    return m_bIsPlaying;
+  }
+
   Void seekAbsoluteEvent( UInt new_frame_num );
   Void seekRelativeEvent( Bool bIsFoward );