I couldn't find on the Internet if the CTRL key was disabled on purpose or if there is an issue with your PC. Typically, you can check this by installing the Impart 32 on another PC and observe its functionality.
Of course, there is the possibility that CTRL key was disabled on purpose due to unknown reasons. If you still have it installed, go to Help > About and use the available details to get in touch with the developers, if they're still available.
