Just to clarify, is it just impossible to download attachments from the archived forum?
I tried editing the link like so, and in some other ways and was unsuccessful:
@Mark Some attachments are downloadable,. others aren't. It depends on how the the file was originally attached. For example, take this parts thread. All the files below each image are dead, but the files attached to the bottom of the post work. (They've been re-uploaded) This is a side effect of how the forum was archived. Unfortunately your only options to find dead files are to look in other sources (such as the Repository archive) or ask others.