Once the Comparison Expert is launched, CATALYST compares all the resources for the selected Active Object(s) against another selected TTK. As the Expert performs the comparison, all differences are listed in the Comparison window under the respective groups: Different, Added and Removed. Those groups are collapsible & expandable via the left arrows:

Clicking a comparison hit in this window opens the resource in Project comparison view:

Use the Project Comparison window to view and navigate the results of the comparison. This window is located on the left edge, alongside the Navigator window in the Alchemy Project Environment.

Click the button to lock the window in place, allowing you to navigate the compared resources in the same way you do in the Navigator window. The default anchored position is between the Navigator Window and the Workspace window. Restore the default windows position in the User profile.

The Project Comparison window can be configured to show the results by resource list (default) or in Groups view. Click  to toggle between the 2 views.
Showing the results by Group organizes the contents to display in collapsible headers; Additions, Deletions, Differences and Similarities, depending on your selection in the Options tab.

While working in the Project Comparison mode, the header of the workspace area is colored to match the Project Comparison window. This color is customizable in the User Profile. The default color is a light purple.

1 Select the resource in the Project Comparison window to view its contents in the workspace window.     2 Use the Filter dropdown to show only the relevant segments for your selection.     3 Opt to view the source text (Original) or the Translated text for the selected resource in the Project Comparison window. If the TTK project contains untranslated text and you select Translated in the View dropdown, CATALYST displays the original text for any untranslated segment. Remember untranslated strings in CATALYST match the source until it is edited or leveraged.     4 The Comparison Expert always displays the Active TTK project on the left side and the compared TTK project on the right. The location on disk for each compared project is displayed in the header bar. This makes it easy to check which TTK files are compared and which is the Active project currently opened in CATALYST.     5 Selecting individual segments marked different (in red), the Translator Toolbar display the text with the Active TTK at the top and the compared TTK at the bottom. It also displays differences in Properties values in the Properties window.   The differences are highlighted for easy comparison.   Those fields cannot be edited. It is however possible to bring the translation from the compared TTK into the Active TTK via the context menu in the workspace window. See Working and editing the active TTK section below.

Bot the Project Comparison and the Project Workspace windows display the differences using colors. The colors used as Red, Green and Blue. With black representing no difference.

Working and editing the Active TTK

At any point you can switch from the Project Comparison view to the standard workspace by clicking on a resource in the Navigator Window. And return to the Project Comparison by clicking on a resource in that window. Clicking a comparison hit in the Results window also sends you to the Project comparison view and opens the matching resource.

This allows to edit the Active TTK while comparing with another TTK. May be the previous TTK which contains the source file of the previous build you localized in CATALYST.