What is .KTH file?
Presentation theme file used by Keynote, an Apple iWork program used to create presentations; contains the default graphics, fonts, and layout settings for a presentation; used for saving presentation templates.
To open a Keynote theme, select File ? Choose Theme... from the application menu, or select a theme from the Theme Chooser when the application starts. You can save custom themes by selecting File ? Save Theme....
Custom KTH theme files are saved to the following directory by default:
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