Within report cards, when browsing the options for how to print student names, if you want to print the student's 'nickname' (which they are changing the language to 'preferred name') then a student who doesn't have a nickname will not have a First Name printed. There should be an option to have the nickname as the default and if there isn't one, then it prints the First Name.
There is now a name format option for Preferredname|Firstname Lastname. Selecting this option will print preferred name if one exists, otherwise will print first name.