Still in development, most of us have lost a fair amount of free time recently. Most of the recenet work which is still in an unstable experimental branch is related to reducing map load times, and reusing media instead of reloading it. I'll take a look at those issues. Off the top of my head I'm not sure what happened to m_accel (did we have it before?). It's not a feature I use but I know others do. Also will take a look at the bind thing, as that was definetly unintentional.
We've never had mouse acceleration support, since that is platform-specific and not available to us through SDL. We would have to roll our own implementation of it, and to be honest, in 15 years of FPS gaming I've never once cared to have it (so I probably won't spend time building it).
There likely are issues with the key binding system. Thanks for reporting those; they should be easy to fix. As wickedshell mentioned, most development work is happening in an "experimental" branch that will not be released until it is stable.
I've had a lot of major life changes going on in the last 6 months, so Q2W development has been sporadic lately. But it will continue, for sure. Pop by IRC if you'd like; the team is still there.