Hi @jmfeng,
From the error it seems like you are using the older version of OpenSpecimen i.e. v1.x. We would suggest you to try the latest release of OpenSpecimen i.e. OpenSpecimen-v2.4. This is fully rewritten using the latest technologies. Its pretty lightweight and easy to deploy and configure.
You can checkout the demo site at http://demo.openspecimen.org/ or how to get OpenSpecimen-v2.0?
Regarding the error: Seems like the property load.balancer.url is not set correctly. Please make sure that the value should be set the actual URL you use to access the application. In you case it should be set to https://cat.unmc.edu/openspecimen/
You can directly update this property in jboss/server/default/catissuecore-properties/caTissueCore_Properties.xml file. Restart the jboss after this change.
~Nitesh