Version 0.13.1 follows shortly after 0.13.0 and fixes a bug introduced in version 0.13.0 in our new handling of predictive nodes in MCMC. The bug could affect MCMC results when using version 0.13.0 in models that both (1) have predictive nodes and (2) have multivariate nodes.
If you have already installed 0.13.0, please upgrade to 0.13.1.
-Chris (for the NIMBLE development team)