I have tired to upload your waveform to and what is interesting, even though the character limits have allegedly been exceeded, the waveform must have been uploaded!
This is what I receive when I first tired to upload your waveform
Screen 1
This suggests either you can amend an uploaded waveform as you requested or the file already exists in the "local" selected folder path (I think the latter)
When I selected "Yes" at the above screen I received the identical message to you
Screen 2
Rather than try to discover where the error lies I will create a bug report using your file as a prime example
I will then assign the bug to the relevant software team and will feedback ASAP here