1) No command-line, it's from GUI
2) Maybe not.
3) Doesn't apply.
4) Not related.
5) Thanks for the advice, but the site I'm downloading from seems to be
playing ball.

Cool, it just had numbers to select from, wasn't apparent that I could do a
manual entry.

Yup, mine looked like step 4 - but didn't change for hours.  Just stood there,
saying it was receiving, but when my other applications were off, my
connection said I wasn't downloading a thing.

Currently trying it again, and while bytes are moving at the top, it's just
re-downloading each file that I've already got - and there's no upcoming queue
so that I can select 'skip' before it starts clobbering the existing (70)
files.  One of the first times around it used to do .tmp files (which I could
then skip, and clobber the small partial .tmp) when starting a download, but
it's not doing that this time.