The original version of Oclarity was designed as an AddIn for Rational Rose. It has seamless integration with the user interface of Rational Rose.
This version is no longer maintained but you can still download and use it free of charge.
Download link: Setup Program for Oclarity for Rational Rose
Download link for the manual: Manual for Oclarity for Rational Rose
When you are asked for a license key, you should enter this string:
60 63 53 58 5d a6 68 75 91 33 94 46 89 4d aa ea 68 83 2f