add Dance Maniax and Technomotion support

stepmania/src/ScreenDemonstration.cpp

@@ -38,6 +38,7 @@ bool PrepareForDemonstration()		// always return true.
 	case GAME_PARA:		GAMESTATE->m_CurStyle = STYLE_PARA_SINGLE;			break; 
 	case GAME_DS3DDX:	GAMESTATE->m_CurStyle = STYLE_DS3DDX_SINGLE;		break;
 	case GAME_BM:		GAMESTATE->m_CurStyle = STYLE_BM_SINGLE;			break;
+	case GAME_MANIAX:	GAMESTATE->m_CurStyle = STYLE_MANIAX_SINGLE;		break;
 	default:	ASSERT(0);
 	}