Change Number of Items to Display : inactive

[dex]

Hi all !

FCG works fine but I would like to change Number of Items to Display.

Actually i've 10 Items to Display and i would like to display only 7 Items but nothing changes on my page.

I've tried to clear cache and try with an other navigator and nothing changes.

My question : to change this value, does FCG need to write in files (because chmod has been changed on my site) ?
Thank you !

[dex]

Ok works now but i don't know why