@Positron I look forward to seeing what you come up with!
I've uploaded a new version.
Of the issues mrmixer identified, I fixed the client not quitting correctly when it fails to setup the UI (it does indeed require OpenGL 3) as well as the "Send Tone" option not working if you do not have a microphone connected (or some other audio input device).
@mrmixer: I managed to find and fix at least one issue where the "Send Tone" option would cause 100% packet loss after being toggled off, but that may or may not have been the issue you were experiencing.
I've updated the links on the original post, but for convenience: