In "18.10.6. Example" in jBPM 7.5.0 doc (https://docs.jboss.org/jbpm/release/7.5.0.Final/jbpm-docs/html_single/#_example_4), following system property names are incorrect:

kie.keystore.server.alias
kie.keystore.server.pwd
kie.keystore.ctrl.alias
kie.keystore.ctrl.pwd

Their prefix should be "kie.keystore.key" instead of "kie.keystore", according to previous section of the doc.