So, first this is run once:
carriage.move(dir,false,false)

dir is the direction it goes in
false is dont simulate, actually move
second false is to move the controller with it.

My best guess is it then gets passed to this:
public Object[] callMethod( IComputerAccess computer, ILuaContext context, int MethodIndex, Object[] Arguments ) throws Exception{
        try
        {
            switch ( Commands . values ( ) [ MethodIndex ] )
            {
                case move :

                    AssertArgumentCount ( Arguments , 3 ) ;

                    SetupMotion ( ParseDirectionArgument ( Arguments [ 0 ] ) , ParseBooleanArgument ( Arguments [ 1 ] , "simulation" ) , ParseBooleanArgument ( Arguments [ 2 ] , "anchoring" ) ) ;

                    break ;

                case anchored_move :

                    AssertArgumentCount ( Arguments , 1 ) ;

                    SetupMotion ( ParseDirectionArgument ( Arguments [ 0 ] ) , false , true ) ;

                    break ;

                case check_anchored_move :

                    AssertArgumentCount ( Arguments , 1 ) ;

                    SetupMotion ( ParseDirectionArgument ( Arguments [ 0 ] ) , true , true ) ;

                    break ;

                case unanchored_move :

                    AssertArgumentCount ( Arguments , 1 ) ;

                    SetupMotion ( ParseDirectionArgument ( Arguments [ 0 ] ) , false , false ) ;

                    break ;

                case check_unanchored_move :

                    AssertArgumentCount ( Arguments , 1 ) ;

                    SetupMotion ( ParseDirectionArgument ( Arguments [ 0 ] ) , true , false ) ;

                    break ;
            }
        }
        catch ( Throwable Throwable )
        {
            throw ( new Exception ( "no such command" ) ) ;
        }

        Error = null ;

        Obstructed = false ;

        try
        {
            while ( MotionDirection != null )
            {
                wait ( ) ;
            }

        }
        catch ( Exception exc )
        {
            //exc.printStackTrace();
        }

        if ( Error == null )
        {
            return ( new Object [ ] { true } ) ;
        }

        if ( Obstructed == false )
        {
            return ( new Object [ ] { false , Error . getMessage ( ) } ) ;
        }

        return ( new Object [ ] { false , Error . getMessage ( ) , ObstructionX , ObstructionY , ObstructionZ } ) ;
    }

The first time around everything works fine, but the second time, using the EXACT SAME function, without the program even running, the "no such command" exception is thrown.