I have a list of 1025 URLs all from the same server. 

I have to mirror all of them in one go so that there won't be any duplicates.

Trouble is, the MemoBox in HTTrack does not accept more than 64 kbytes (my
URLs amount to 72 kBytes).

I think the problem lies with the Memo and not with HTTrack, so if HTTrack had
a way to import (or rather, directly use) URLs in an external .txt file, my
problems would be over.

Here's I am hoping that the developer will agree and implement that feature.