Description:
In BW 5.2.0 online doc, it says:
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Setting Custom Engine Properties in Deployed Projects

TIBCO Administrator is responsible for deploying process engines in a production environment. TIBCO BusinessWorks provides a file for specifying any custom properties you wish to set in deployed engines.

The bwengine.xml file is located in the lib subdirectory of the TIBCO BusinessWorks installation directory. For example, on MS Windows machines, this file would by default be located in c:\tibco\bw\&ltrelease_number>\lib\bwengine.xml where &ltrelease_number> is the release number of the currently installed TIBCO Designer.
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However, if user tries to edit "\tibco\bw\5.2\lib\bwengine.xml", new properties would not be reflected upon building the .EAR file.

If user tries to edit "\tibco\bw\5.2\lib\com\tibco\deployment\bwengine.xml", new properties would be reflected upon building the .EAR file. And this behaviour is the same as BW 5.1.3.

The correct location should be "\tibco\bw\5.2\lib\com\tibco\deployment\bwengine.xml".
Symptoms:

Cause: