SharePoint 2010 BDC Error

Sooo, I have this lovely app def file, that uploads perfectly.  But when I go to use one of the entities in a list column, I get this interesting issue (notice that I don't get columns, but the first named TypeDescriptor):

 

Fair enough, I'll remove the wrapper from around my return
columns from the query. This USE to work in 2007 by the way:

<TypeDescriptor
TypeName="System.Data.IDataRecord, System.Data, Version=2.0.3600.0,
Culture=neutral, PublicKeyToken=b77a5c561934e089"
Name="ProductDataRecord">
<TypeDescriptors>
….Column descriptors….
</TypeDescriptors>
</TypeDescriptor>

Re-upload, and whalla…it works like it did in 2007!

 

But, on adding an item with item resolution, you get this lovely error:

The root TypeDescriptor with Name 'Reader' belonging to Method with Name 'Find_Customers', of Entity with Name 'Customers' and Namespace 'Northwind' has a TypeName that is not assignable to System.Data.IDataReader or is not a Collection TypeDescriptor, which is necessary when using LobSystems of Type Database.

Fair enough, sooo, I go and change it in the app def file:

<TypeDescriptor TypeName="System.Data.IDataReader, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" IsCollection="true" Name="Reader">

And on upload, you get this lovely error:

ReturnTypeDescriptor of MethodInstance with Name 'Find_Customers_Instance' on
Entity (External Content Type) with Name 'Customers' in Namespace 'Northwind'
should not be a Collection TypeDescriptor for MethodInstances of Type
'SpecificFinder'

Oh yeah baby…a catch 22 loop!!!  Anyone? Bueller?  Bueller?

It just keeps getting better doesn't it???
Chris