The only possible reason I can think of, is you either moved to another airport before saving that one, or the program crashed exactly while it was saving the file.
What happens if you Restart Couatl ? Do you see still the .INI file referenced there ?
I've restarted Couatl and tried again.
The first time, no profile was referenced (file error 1.png).
I did a small change and applied, the file .ini is shown, but at the folder the file itself it's not created. (file error 2 and 3).
After that I closed the customization screen, reopened, the ini path was still there, but after i've done another change and apply, it disappears. (file error 4). If I done another change, it will create another .ini path with a different suffix.
I've tried in another airport (file error 5 and 6). When I do others changes in the customization, the .ini keeps the same suffix. (error 7
I'm attaching the log file.