It had escaped my attention, but already in 2016 a Red List of terrestrial invertebrates for Cuba was published. It deals with Mollusca, Insecta and Arachnida.
The chapter on molluscs contains species of Cerionidae, Annulariidae, Cepolidae, Helicinidae, Urocoptidae, Orthalicidae, and Pleurodontidae. In total 88 (sub)species are listed and assessed according to the IUCN criteria. This < 10% of the species known from the island.
A very useful source of information and a good basis for further research.
Hidalgo-Gato González, M.M. et al., 2016. Libro Rojo de invetrebrados terrestres de Cuba. – Editorial Academia, La Habana, 241 pp. Link