This will need Miro's analysis. But a work-around:
1. Create a Calibri style.
2. Exit the program. (Never edit the .ini file while the program is running because NC Pro will overwrite your changes the next time it exits.)
3. Open your notecase_pro.ini file in a text editor that supports UTF-8 encoding. (You can find the file's location on your system using the Help file > Installing and Upgrading > NoteCase Pro File Locations > .notecase Directory.
4. Search for your Calibri style in the .ini file. It should read something like
211: StyleName_1=Caliibri 20 (where 20 is your font size.
5. If it says Calibri Light, delete the "Light."
6. If you also delete the font size, the effect will be to inherit the font size of the surrounding text, which is probably your default text font size. This is handy if you open the same document on a different machine that has a different screen resolution.
7. Save the .ini file to disk.
8. Relaunch the program.
9. Should be joy.