OWC pivot & OLAP

[Effie]

Hi!
i'm trying to connect to a cube via owc/pivot.
the connection is working, and i can add fields manualy to the grid by
dragging.
How can i pre define (by code) what fields will be loaded?
this command--> pivot.DisplayFieldList = true
display the fields and i can drag them.

this command --> PivotView.FilterAxis.InsertFieldSet
PivotView.Fieldsets([year])
do not placing the year field on the filter grid (no error)

TIA, Effie