This query seems perfectly fine and I believe it is working with the latest version of OpenAccess ORM.
Here is the query I used for testing:
EntitiesModel context =
var result = context.Products.Join(context.Orders, outer => outer.CategoryID, inner => inner.EmployeeID, (outer, inner) =>
ItemId = outer.CategoryID,
Data = outer,
StateForm = inner,
InventoryId = inner.OrderID}).ToList();
Could you confirm that this query actually resembles the query you had written on your side. If that is so, it means that even if a problem was available in the version you are using, it has already been fixed. I suggest you to really use the latest version of Telerik OpenAccess ORM sa it contains lots of fixes and improvements in all areas and Linq is especially one of them.
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