This hotfix can be downloaded from the SFDC Customer Portal Web UI, using your username and password for support.tibco.com. Once logged on you can find the hotfix under Download Menu:

AvailableDownloads/BusinessWorks/Plugins/REST_JSON/2.1.0/hotfix-16

Below is a summary of the update included. Please refer to the associated readme document for any additional information.
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Closed Issues in 2.1.0_HF-016 (This Release)

Defect ID: REST-1942
           A property based fixed has been added for the Invoke REST API activity failed to error out even after getting the 500 status code.
           
           The above-mentioned issue has the property-based solution.
           The name of the property is "com.tibco.plugin.restjson.ThrowServerSideExceptions".
           The user needs to set this property to "true" to enable the fixes. The default value is �false�.
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