Talk:Self-install-existing
From Amahi Wiki
I think it should be mentioned that if you already have MySQL installed, and you've changed the localhost root password to something else than the default blank, you'll need to change the value of DATABASE_MAIN_PASSWORD in /usr/bin/hda-new-install to that password. If you don't, install will fail.
If you don't uncomment this line too:
do_system_silent "mysqladmin -u #{DATABASE_MAIN_USER} password '#{DATABASE_MAIN_PASSWORD}'"
this will fail, but I don't think that will stop a successful install.
Also, I think it might be good to mention that /etc/samba/smb.conf will be overwritten by Amahi, so if you want to keep yours, you should back it up first.