Need help with Entity Model & new stored procedure

Hello,

I get this error:

The type parameter 'NopSolutions.NopCommerce.BusinessLogic.Products.CustomDescriptionLine' in ExecuteFunction is incompatible with the type 'NopSolutions.NopCommerce.BusinessLogic.Data.Sp_ProductCustomDescription_Result' returned by the function.

Details:  I have created a SP which return 0 or more rows of data (two columns) given a ProductId as input.

I have also updated the 'NopModel.edmx' file including creating a complex type as well as 'Import Function'.

What I am trying to do is very similar to the way the 'BestSellersReport' works.

Can someone please help.  I hate to admit it but I am bordering desperation!