Custom sorting for calculated table (circular error)

Hi,

If possible, one of ways is to create sort column in power query editor.
Please check the below picture and the attached pbix file.

let
    Source = source,
    #"Sorted Rows" = Table.Sort(Source,{{"CATEGORY Nr.", Order.Ascending}, {"NAME", Order.Ascending}}),
    #"Grouped Rows" = Table.Group(#"Sorted Rows", {"CATEGORY Nr."}, {{"Count", each Table.AddIndexColumn( _, "index",1,1)}}),
    #"Expanded Count" = Table.ExpandTableColumn(#"Grouped Rows", "Count", {"NAME", "index"}, {"NAME", "index"}),
    #"Added Custom" = Table.AddColumn(#"Expanded Count", "sort_order", each [#"CATEGORY Nr."]*1000 + [index]),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"index"}),
    #"Changed Type" = Table.TransformColumnTypes(#"Removed Columns",{{"NAME", type text}, {"sort_order", Int64.Type}})
in
    #"Changed Type"