Does the Steam version still get any updates?
Rarely, but it does. Only when DH bothers to push versions out to Steam. Usually it's version updates not bugfixes, tweaks and minor additions that get pushed. So don't expect to see any further updates to this via Steam until version 0.77.0 (or above) gets released and then wait another couple of weeks for it to get pushed to Steam.
But there does exist a sneaky workarround:
Download the version here and delete the contents of steamapps\common\Breeders of the Nephelym Alpha.
Then unzip the downloaded archive into that now empty folder.
Steam can't force you to downgrade. It'll load just fine.