One possible cause for the failure at Executing .\changepassword_thingworx in the log happens when there has been a previous install attempt on this server. The previous attempt may have left incompatible info in the Temp folder that interferes with the encryption of the password. To get past this condition:
Run the navigate uninstaller
Create a new Temp folder
Set environment variableTMPto location of new Temp folder
Try the install again
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