>This isn't possible - but broken files should not occur 
>very often anyway? (except with overloaded servers, or 
>network problems?)

But when you HAVE GOT this problems (poor dial-up),
mirroring anything larger than 20Mb with couple zips grater
than 1Mb becomes true nightmare. For now, I solve it by
dropping URL to such files to my Download Manager manually.
But this can become very annoying when you dealing with
complex projects. 
  So what about adding to HTTrack plugin interface? You can
concentrate on parsing engine which always will need hours
and hours to spend on, and many people can write plugins to
allow themself to get files from I-Net in favorite way. This
plugins, for example, can be just wrappers for Download
Manager (WGet, ReGet, FlashGet... to many to remember them
all), or they can implement their own download engines.
  If you think, that there is anything to discuss about
this, feel free to E-Mail me.