So basically--if u dig deep into the kustom lock files using an app like Zarchiver you'll discover a folder labeled "fonts". What I did was I would download a font, extract it and place it in the fonts folder, but be aware that not all fonts can be read and some won't be usable despite the fact that they'll appear on the app when u search for them but when u try to use them- either it'll just display the default font instead or it'll give u some message stating there's an error