I doubt anyone will pick up on this but the problem with Sound Editor in general appears to be poorly set up software. Sound Editor has changed very little over many years and I have come across similar issues in the past. These were resolved by opening and closing another program which I'm guessing had the effect of clearing out a portion of RAM or data area that Sound Editor, for whatever reason, had not set up, reserved or cleared correctly.
In the Sound Editor with Easy Media Creator 10, editing would freeze on a particular track.
In the Sound Editor with NXT Pro 5 it is the noted fault: falls over at 99% after recording is completed and you hit "Stop".
I have found that if you run up Libre Office Writer Document and then close it without typing anything, or similarly run up WordPerfect X8 and close it, Sound Editor does NOT crash.
I know it's a workaround but, maybe, just maybe, a software engineer at Corel might finally revisit the Sound Editor software and see where the programming error lies!!
Thank you if you take the time to read this.