Hi!
I think I've found a bug:
I'm mirroring currently a website > than 2GB and I 
noticed that the project size (in bytes) in the title 
of the window turns into minus and starts counting 
down. Maybe you declared the variable to small and 
redeclare it. Of course it's not a really important 
problem.
I use the following system:
Windows 2000 (german)
WinHTTrack Website Copier 3.15
Thanks in advance and keep up the good work,
Sebastian Schuon