> I want to download all file from a URL, but only file 
that 
> have been modified on that given day? How do I go about 
> telling HTTrack to download only files that have modified 
> date = today? (files names change on a daily basis)!!

You can't - HTTrack will make its best to mirror modified 
files only, that is, files that were modified since last 
mirror, but you can't control exactly the update process.