Well, a later release date does not automatically mean that it won't work with an earlier device.

I've found a shorter opening line for testing:
None of the Conchess versions have 1.b3 in their internal books, so they start thinking. Now with the L16 loaded only the 2 Amsterdam versions immediately answer with 1... e5, but not any of the others.
So the L16 is in fact only used by the Amsterdam version (although it also loads on the others without problems), and your book settings in the Conchess driver are correct!