Wouldn't that be because current dev branch requires the 0.51.1 installation, rather than the latest stable 0.49?
For 0.49, I think you can only go with the master branch of the mod (
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), without the new additions that are based on 0.51 code. I'm not even sure if you can pull bugfix that does NOT require 0.51, now, either - both master and dev branch appear to have commits updating to that version, and from what I've noticed those are not interchangeable between base code versions (0.49 and 0.51) due to re-organizing of variables and scripts.
So basically the choice is to either go with the one-pack-install from the OP here for 0.49 (with no newer content than when it was compressed, can't apply anything from mod's dev branch on it), or go with the whole installation I described in that wall-of-text post of mine for the new content running on 0.51.
Unless I'm completely misunderstanding things here as usual.