Cannot flag multiple tracks as "Default" or "Forced".

[nx6]

I only recently realized I can edit existing tracks for flagging as part of a MKV Muxing Batch GUI process, but I have found I am only allowed to only mark one track in all as Default or Forced. In the case of a file with multiple tracks for multiple languages, this means I cannot flag the audio/sub track for each language, as per Matroksa spec.

Can you adjust the function to allow checking as many tracks as wished for these flags?