Kartu,
At the end of the installation guide you say to put your fonts in the FONT directory and reflash. That directory, as you know, is for system, lrf, lrx and I think any file without embedded fonts that is read by the reader. In order to work, these fonts have to precisely named and formatted. I placed a comment that helps explain this after the guide. I also provide the factory default Dutch font and the free fontin font already named and tested for use by all.