First of all: WHAT GREAT SOFTWARE!! Really, I love it. It just works great for
me.

1.) Sometimes a server returns a message ('system overloaded', 'temporary
unavailable' etc.) without redirecting, ie. the filename doesn't change, but
it's just a few hundred bytes and contains html. So an additional option for
the 'update hack' option would be nice. As I understand it, right now only
files with changed filesizes are re-downloaded. How about the option to
re-transfer only when a.) the new filesize is BIGGER than the old one or b.)
the filesize is bigger/smaller, but above N bytes (to weed out the error
messages mentioned above).

2.) Managing of mirrors... the dropdown-list becomes quite unhandy when you
have several mirrors and want to update them every now and then. Basically a
listview would be great, with sorting by name, last update, size,or number of
files?