The main developers web site for Gnash is located on the Free Software Foundation's Savannah project support server at this link. That is where bugs can be filed, or you can view the sources in CVS.
The Gnash Wiki is here.
I'm playing with DotProject. You can see my minimal setup here. I'm starting to think we won't actually use it.
Instead we'll use the Task Manager on the FSF's savannah server.