Custom Leanback Keyboard for Universal Remotes

How difficult would it be to modify the Leanback keyboard so that it could be used with universal remotes? My Nexus Player is connected to a Flirc USB infrared dongle which I use with a Philips SRP5107 universal remote. I have my universal remote's main OK button mapped to emulate the ENTER key on a keyboard and this works fine in most cases but not with the Leanback keyboard. It isn't a problem with some apps like Netflix or Kodi that have their own keyboards but for the Leanback keyboard that's used in apps like Google Play and YouTube, pressing the OK button on a universal remote causes that on-screen keyboard to close off. This problem does not exist with the original Nexus Player remote's select button because it is context-sensitive. Can the Leanback keyboard somehow be modified to *not* close but rather type the selected on-screen key when it detects an external ENTER key / OK button being pressed?