Okay I figured it out. Since we're using the DOS loop it can make the correct
filenames:

for /L %a in (1,1,5) do "C:\Program Files\WinHTTrack\httrack.exe" --get
<http://forum.xda-developers.com/showthread.php?t=389106^&page=%a> -O1
"J:\Temporary\Download" -N "Topic-389106-Page-%a.html"

Gives me:

Topic-389106-Page-1.html
Topic-389106-Page-2.html
Topic-389106-Page-3.html
Topic-389106-Page-4.html
Topic-389106-Page-5.html

plus the .readme files.


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