blavaan 0.5-4 is now on CRAN, including bug fixes and a sampleData() convenience function for generating data from the posterior (or prior) distribution.
The website also includes some new slides from my NCME workshop on Bayesian modeling last week, which illustrate much of the newer functionality in blavaan. An aim was to present and illustrate SEM as a model of raw data, as opposed to solely a model of covariance matrices. See the first bullet of this page:
Ed