Thanks for your feedback. Regarding n°1: I liked the idea of a tiny version as well (the widget updates itself). I had this once implemented but got some problems trying to only send ajax requests when the current tab has the focus. Otherwise this could mean a lot of ajax requests to your server if each user opens a lot of tabs. Cannot recall if I posted about the problem here on q2a.
Furthermore, I remember that my users told me they don't care about a "live widget", their main "tool" is the liveticker page. They have it constantly open and are always following it ;)
Regarding n°2: Yes, you are right. I could setup color options if more people request this. But the color scheme provided for the ticker (question light green, answer light blue, comment gray, best answer yellow) has proved to be very efficient for my users at http://www.gute-mathe-fragen.de/liveticker