Insert new record into database using Entity Framework

I have a table like this in my database:

[id] [uniqueidentifier] NOT NULL,
[user_id] [uniqueidentifier] NOT NULL,
[download_type] [nvarchar](50) NOT NULL,
[download_id] [nvarchar](50) NOT NULL,
[download_date] [datetime] NOT NULL,
[user_ip_address] [nvarchar](20) NOT NULL,

The id is described as the main key.

This table needs to have a new record added to it. Here is the code I'm trying to run but can't.

CustomerPortalEntities_Customer_Downloads dbcd = new CustomerPortalEntities_Customer_Downloads();

public ActionResult Download(string id)
{
    var collection = new FormCollection();
    collection.Add("user_id", Membership.GetUser().ProviderUserKey.ToString());
    collection.Add("download_type", "Car");
    collection.Add("download_id", id);
    collection.Add("download_date", DateTime.Now.ToString());
    collection.Add("user_ip_address", Request.ServerVariables["REMOTE_ADDR"]);            

    dbcd.AddToCustomer_Downloads(collection);

    return Redirect("../../Content/files/" + id + ".EXE");
}

The line dbcd is where I encounter the problems. AddToCustomer Downloads(collection);

The best overloaded method match for 'CustomerPortalMVC.Models.CustomerPortalEntities_Customer_Downloads.AddToCustomer_Downloads(CustomerPortalMVC.Models.Customer_Downloads)' has some invalid arguments

Argument '1': cannot convert from 'System.Web.Mvc.FormCollection' to 'CustomerPortalMVC.Models.Customer_Downloads'

What must I alter to make this work?