Thanks for inquiring Aspose.Slides.
I have observed the information shared by you and request you to please share the working sample project reproducing the issue along with source and generated presentations. Please also share the steps for reproducing the issue on our end as well. I also suggest you to please try using Aspose.Slides for Java 17.5 on your end first as well.
Thank you for sharing the detailed information. I have extracted the source and generated presentations and have been able to observe the missing part in saved presentation NotesMaser XML file. An issue with ID SLIDESJAVA-36444 has been created in our issue tracking system to further investigate and resolve the issue. This thread has been linked with the issue so that you may be automatically notified once the issue will be fixed.
We are sorry for your inconvenience,