data selection

Dear BW Experts,

I've a question on data selection in infopacks.

Is it a fact that routine / variables will override whatever I enter in the 'From Value' / 'To Value' selection fields in the infopack? that is hardcode it.

Is the 'Use conversion routine' check box to activate the use of routine in the selection? How to view the routine to edit? Can selection values (from, to) be controlled to allow strictly certain values only despite manual entering in the selection fields of the infopack?

Basically, can BW be secured like R/3 to field level for all things? How would you secure the data selection when anyone can enter anything in the selection?

Seeking your advice.

regards,

Pascal