Model class selection cookbook example with nested SBM fails on custom graph

Dear all,

after trying for a few days to resolve this myself, I decided to ask for
help here.

The cookbook example on model evidence for the nested example fails on all
my graphs, but works with the original["lesmis"] graph.
The code is exactly as in the cookbook example
. The unnested SBM does work with every graph I tried.

Here's the error message, which is triggered in the call to

This is an old release. Please first upgrade to the newest release before
reporting a bug.