No, we have not customised it.
That's the way it comes this SVN from eAthena. It's the version we had our last SVN, as this SVN's version was once again, riddled with bugs in eAthena's release.
The only "customisation" the Sign Quest we have in currently are the fixing of several bugs, none of which were around the Dance part.
It is passable however. We've tested it and done so several times in the past (all with this SVN).