Clearing your font caches (see if you can find a copy of Cocktail old enough to run on that system) might help.
Many thanks for your prompt answer to my question. As a semi-retired professional photographer I work continually on a MacBookPro OS 10.10.4 with Photoshop CC 2015 and Lightroom CC 2015 and occasionally on my old Mac G4 Power PC with OS 10.5.8, where I am concluding a 315 page photobook with InDesign CS3. For the time being I don´t intend to buy InDesign CC 2015, since I have practically concluded the book project.
Please excuse my ignorance, but I don´t understand your advice: I don´t know any "Cocktail" software nor do I know where to find it. I also ignore how to clear the font cache of the G4 Power PC. I would like to recover the missing fonts that must exist somewhere, because I haven´t thrown them into the trash.
Hoping to hear from you again I appreciate your assistance.
Here's a link to the Cocktail utility:
There are links on that page to versions of Cocktail supporting Mac OS X back to 10.6. You might have to update your system to 10.6.
That's one of the problems of old software: It becomes hard to do proper maintenance.