Have you designed only upper case? Or only lower case?
Font preview software, such as “Font Book“ on OSX will, by default, show a preview string that contains mostly lower case letters. For example: “Five big quacking zephyrs jolt my wax bed”.
– If you have only designed upper case, you will only see the F.
You can still install your font and type with it, but only using the letters in the case you have designed.
Note that in the FontStructor, in advanced mode, there are commands in the menu to copy upper case to lower case and visa versa – this can be a useful shortcut if you are only interested in designing one case.
Please contact us if you can’t find the information you’re looking for here.