Csv import update

[luajmare]

Hi guys, I have a big problem, in my store i have 400 product i ussaly import them with csv import from prestashop(1.4.9).Ok the problem is, the weekly update , because the new offer from my manufacturer changes dramaticaly.This week i made the csv files with features for layerd navigation,but next week i need to make another csv file with features this operation take me 2 days.I need to know if it is a way in prestashop to report the new products added whitout features and the rest with features not appear in the report.

Sorry for my bad english.Cheers oooo and thanks in advance