Custom WPF screen keyboard instead of windows touch keyboard (TabTip)

Question

I made custom WPF screen keyboard. Is there any possibility to use it instead of TabTip.exe? When I replace original TabTip.exe with my custom keyboard in directory C:\Program Files\Common Files\microsoft shared\ink\ I am able to run the keyboard from the task bar using keyboard button:

Feature that I am trying to recreate is showing/hiding keyboard, when some UI elements are clicked (ex. input in chrome/edge or textboxes in Windows applications). I spent some time using Process Monitor and found two registry records which values are changed when TabTip.exe is triggered to show/hide (they are located in HKCU\SOFTWARE\Classes\LocalSettings\Software\Microsoft\Windows\CurrentVersion\AppModel\SystemAppData\MicrosoftWindows.Client.CBS_cw5n1h2txyewy\HAM\AUI\InputApp\V1\LU):


Value of ICT changes when TabTip is going to be displayed on the screen, ITT when TabTip will be hidden. When TabTip.exe is replaced with my keyboard these values do not change. I don’t know if this information is important in this case.

If anyone could point out any ideas, I would really appreciate it.