1)If you add an empty text region to a text region and save the project, SMath freezes and crashes when you try to open it again.
At the same time, if you add a non-empty text area to the text area, the project will open after saving

2)If you add a text region to the test region and try to select both regions and change the font size of the text regions, SMath freezes and crashes

Wrote

1)If you add an empty text region to a text region and save the project, SMath freezes and crashes when you try to open it again.
At the same time, if you add a non-empty text area to the text area, the project will open after saving

2)If you add a text region to the test region and try to select both regions and change the font size of the text regions, SMath freezes and crashes

This is the error I corrected some users documents time to time.
It requires manually editing the smath file with a text editor.