> I want to download a picture gallery. 
Always post the actual command line used (log file line two)

> I don't want any subfolders at all, I simply want
Site structure = xx in web/xx


> example. Instead the current name of the picture is
> always a string of 
> four letters and numbers_five other letters and
> numbers
> e. g. b4bc_1be45
The image name is what the site named it.
If the url is something like getImage.php?ID=BOAT you could use HTTrack Help:
User-defined structure
<http://httrack.kauler.com/help/User-defined_structure>
to name the images b4bc_1be45-BOAT.typ