Elk 0.5 is not yet released: https://github.com/liveontologies/elk-reasoner/wiki/GettingElk

but it's important that people get to test before it is released, as it is revealing lots of cryptic issues

• ELK 0.5 shows GO has a large number of logical incompatibilities with property ranges geneontology/go-ontology#16524
• Unsatisfiable classes revealed by ELK 0.5 obophenotype/uberon#1455