`$page = Page::make();` instead of `$page = new Page()`; Then we can set proper position...

gistfile1.php

    public static function make(array $attributes = array())
    {
        $model = new static();

        // Workaround to set the position
        if ( ! isset($attributes[static::POSITION]))
        {
            // We set depth to 0 because newly created model
            // via 'create' method has no default closure table
            // attributes and is inserted as a root node
            $model->hidden[static::DEPTH] = 0;

            $attributes[static::POSITION] = $model->guessPositionOnCreate();
        }

        $model->fill($attributes);

        return $model;
    }

    /**
     * Save a new model and return the instance.
     *
     * @param  array  $attributes
     * @return Entity|static
     */
    public static function create(array $attributes)
    {
        $model = static::make($attributes);
        $model->save();
        $model->setHidden($model->getClosureAttributes());

        return $model;
    }