Could not load type RogueSharp.Map

MapGenerator.cs

using RLNET;
using RogueSharpTut.Core;
using RogueSharp;

namespace RogueSharpTut.Systems
{
    public class MapGenerator
    {
        private readonly int _width;
        private readonly int _height;

        private readonly DungeonMap _map;

        //Constructing a new MapGenerator requires dimensions of the map it will make
        public MapGenerator(int width, int height)
        {
            _width = width;
            _height = height;
            _map = new DungeonMap();
        }

        //Generate a newmap that is a simple open floor with walls around the outside
        public DungeonMap CreateMap()
        {
            //Initialize very cell in the map by setting walkable/transparency/explored to true
            _map.Initialize(_width, _height);
            foreach (Cell cell in _map.GetAllCells())
            {
                _map.SetCellProperties(cell.X, cell.Y, true, true, true);
            }

            //Set first and last rows to not be transparent or walkable
            foreach (Cell cell in _map.GetCellsInRows(0, _height -1))
            {
                _map.SetCellProperties(cell.X, cell.Y, false, false, true);
            }

            //Set the first and last columns in map to not be transparent or walkable
            foreach(Cell cell in _map.GetCellsInColumns(0, _width - 1 ))
            {
                _map.SetCellProperties(cell.X, cell.Y, false, false, true);
            }
            return _map;
        }
    }
}