I think that in this case you need to refer to Lecture in your named queries as Lecture because that is the name of the class. You never need to refer to the name of the table anywhere in your code (HQL included) with the exception of the @Table annotation or if you ever do plain sql queries (that is without hibernate).
Try changing your named queries to use the name of the class instead of the name of the table and see if that works.
Thanks for the offer but I think I'll try further with a simple setup and see what I can find. I've put it together in IntelliJ and it's not showing any error messages so I'm going to try reading and writing some data with the queries and see how far I get.