Hello Katerina,
I had a look in the view configuration that you have created and it is in general correct. You have created one view display for each one of the different categories and then you filter them which is in general the way to go.
However the filter criterion that you are using is incorrect. You are filtering using feeds_item: target id when it should be field_indico_event_category_id (if you search for “indico” in the filters search you will find it). Then limit by the ID for each one of the displays as you already do.
For that I will have a look asap.
Konstantinos