Some random questions about display order in group buffer and usage of multiple e-mail addresses

[aa-news]

Hi all,

I've just started using gnus again after some years of absence.  I've
reread parts of the manual without finding answers to some of my
questions.  I hope someone herein can help me.

1. I like using topic mode.  I'm a bit anal about the ordering of topics
   and groups within topics but I was never able to find out whether it
   is possible in gnus

   - to change the display order of individual topics on the same level

   - and to change the display order of groups within topis.

   Could you tell me if it is possible to change the display order and
   if so how?

2. I have several e-mail addresses which I like to use for different
   purposes.  So my next questions are:

   - Is it possible to tell gnus to use a certain e-mail address for the
     From header in news articles on a per group basis?

   - Is it possible to tell gnus to do the same thing on a per mail
     group basis?

   - Is it also possible to get prompted for a From address from a list
     of possible e-mail addresses when posting to certain mail groups?


Thanks in advance,

aa