> we are interested to transform out HTTrack
> downloads
> to the ARC or WARC format.
> 
> Does there exist a utility of HTTRack,
> which directly converts the content of the hts-cashe
> directory (especially of the hts-cashe/new.zip)

The cache is for HTT internal use, ignore it
The mirror is a collection of files, do what you want with them.