If an audio book has over 100 chapters 'Edit MP4 chapters' fails. The error message is:
Could not load info (Unsupported format or corrupted file (invalid index map)) from:
"m4a file" / index: 133
After attempting to load the chapters the m4a file is corrupted. The cue sheet loads fine. All chapters play correctly. It's only when I try to update the chapter info that it fails.
A second issue mostly cosmetic is that when I update the chapter information in v1.3.17 it expands and when I delete the info it contracts. In v1.4.2 it just stays the same. I have to reload the file to see the changes.
Noted, thanks for reporting.