This is being done with a query of a custom view:
// Add the main menu
DataQuery query = new DataQuery()
.From( "View_Custom_OLY_MenuItem" )
.Where( "Type", QueryOperator.Equals, "MainMenu" )
.OrderBy( "NodeOrder" );
viewModel.MainMenuItems = new InfoDataSet<TreeNode>( query.Execute() );
Let me ask another question that may help diagnose the problem ...
Is it possible that the GUIDs for DocumentNodes or any other node could change in a DB upgrade from 8.1 to 8.2?