<p>I'm using Emacs with <a href="http://mfgames.com/linux/csharp-mode" rel="nofollow noreferrer">C# Mode</a> and when I turn on the speedbar, no files show up by default.   I can choose "show all files" on the speedbar mode, but then every .cs file shows up with a '[?]' next to the name.   How do I properly configure speedbar so it shows up with .cs files by default?  How do I get the '[+]' next to each file so I can navigate inside the file?</p>

I used speedbar earlier and got really irritated. I now use
ECB
.
ECB
uses its own buffer for the tree and can optionally show the outline of the CS file in a separate buffer. They all fit in the same frame while Speedbar has its own frame.
I have some
custom stuff
setup for ECB. You can see it here.