I tried version 3.4, but had to roll back to 3.33 for the following reason:

In version 3.33, when encountering a text page with no extension ("filename")
httrack would add ".txt" to the file when saving it ("filename.txt"). This
worked perfectly for me.

In version 3.4, the same page is saved as an html file with a somewhat mangled
filename ("filenamehtml.html"). This is bad. This also makes the file
unreadable since the line breaks in the text file are ignored when being
rendered as an html file since html ignores line breaks, giving you a page
that's one huge paragraph long.

I'm hoping this is a bug and not by design.