Automapper ExpressionBuilder Ctor Parameter Error

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using AutoMapper;
using AutoMapper.QueryableExtensions;

namespace AutomapperTestCtor
{
	public class ClassA
	{
		public string PropertyA { get; set; }
		public string PropertyB { get; set; }
	}

	public class ClassB
	{
		public string PropertyA { get; }
		public string PropertyB { get; }

		public ClassB(string propertyA, string propertyBWithDifferentName)
		{
			PropertyA = propertyA;
			PropertyB = propertyBWithDifferentName;
		}
	}

	class Program
	{
		static void Main(string[] args)
		{		
			var mapperConfig = new MapperConfiguration(cfg =>
			{
				cfg.CreateMap<ClassA, ClassB>()
					.ForCtorParam("propertyA", x => x.MapFrom(y => y.PropertyA))
					.ForCtorParam("propertyBWithDifferentName", x => x.MapFrom(y => y.PropertyB))
					;
			});
			mapperConfig.AssertConfigurationIsValid();

			var listOfA = new List<ClassA> { new ClassA { PropertyA = "Foo", PropertyB = "Bar" } };
			var mapExpression = mapperConfig.ExpressionBuilder.GetMapExpression<ClassA, ClassB>();

			foreach (var result in listOfA.Select(mapExpression.Compile()))
			{
				Console.WriteLine(result.PropertyB);				
			}			
		}
	}
}