> Complicated by the fact that the forum can not be
> overloaded, which is why he downloaded a very long
> time (about 8-10 hours).


Humm, so difficult to track. I have committed a change that should
mitigate/fix this issue, even if I do not fully understand how it may happen:

<https://code.google.com/p/httrack/source/detail?r=1127>