There is only one file type that uses the .KCT extension:
Keyman Developer Customization Source File
A KCT file is a source file created by Keyman Developer, a program used to create, edit, and distribute digital keyboards for any type of language. It contains information about the user interface of a custom keyboard, which includes text, configuration windows, and welcome screens.
You will most likely only come across a KCT file if you have Keyman Developer installed on your computer. The file is created using the Branding Editor included with Keyman Developer. If you are building a custom product installer, the KCT file must be selected when you create the product installer. When the product installer is being built, the KCT file is compiled into a .PXX file.
|Tavultesoft Keyman Developer||Free|
Updated: July 17, 2017