This hot fix 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-01

Listed below is a summary of updates included. Please refer to the associated read me document for any additional information.
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Closed Issues in 2.1.0_HF-001 (This Release)

Defect ID: REST-1448

  Encountered "Invalid Json data" exception in the output binding section of 
  Rest Dispatch and Reply activity for a valid json string.

Defect ID: REST-1451

  REST Dispatch and Reply activity returned an error upon receiving a valid JSON 
  string with escape.

Defect ID: REST-1452

  Special character '€' transformed to '\u20AC' on using Render JSON activity.
  To solve this issue, add the property 
  com.tibco.plugin.restjson.xml2json.unicodeToChar and set it to "true".
  The default value is "false".

Defect ID: REST-1459

  Certificates were not loaded from GV path when Resource URI was set in Input tab.
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