Comparer module does not compare fields of a custom group !

[The Godfather]

​Hi

I created a custom group ( named دوربین کامپکت  ) , then i added some fields which parent is ( دوربین کامپکت ).

I created two products which i used custom group ( دوربین کامپکت ) in both. but when i compare them, fields of the custom group i created (  دوربین کامپکت ) does not show to compare at all.
please compare these two products i'd created for test ( جیجیجی & 2جیجیجی ) http://www.abarbuy.com

so much thanks in advance.

If there's any extension that has this feature, please tell me that. Thanks.