CT&A 6.0 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This software for Mac OS X is a product of The BabelColor Company. The program lies within Design & Photo Tools, more precisely 3D Modeling. We recommend checking the downloaded files with any free antivirus.
From the developer:
CT&A (Color Translator & Analyzer) is a collection of tools specifically designed for the measurement, conversion, and analysis of individual colors or small batches of colors (depending on the tool). The tools are grouped by theme in individually managed windows; these windows are controlled with a menu or toolbar.
You may want to check out more Mac applications, such as CTA Bus Tracker Widget or CrazyTalk Animator, which might be similar to CT&A.