Just wanted to write a quick note to explain why the current nightlies aren't working.
The openwrt servers had an outage recently. As of now, svn.openwrt.org, downloads.openwrt.org and I think lists.openwrt.org are still down.
As the nightly builds feed from svn.openwrt.org, the builds won't start again until svn.openwrt.org is restored. If you've just flashed an image, chances are that you can't install things like luci at the moment - as those are stored on downloads.openwrt.org.
All in all, when things are back in working order, things should just magically start working again.