I checked a bit more about the predefined symbols. I will be able to add them, but it needs to be in a category. I already have "Export by Category" (which you may test already with .gpi files). I will add "Export by Symbols". All POI with the same symbols will be regrouped together with that symbol on the map. The first level of category will be the symbol name.

For example:

Parking
- Poi 1
- Poi 2
- ...

Rest Areas
- Poi 1
- Poi 2
- ...

etc...

I think it will be a good start.

I also worked on adding WAV files (with the same name as the poi file, but with a .wav extension). WAV needs to be converted to 44100 Hz, so I support only 44100 Hz audio wav for now. It is done, but I need to test it first. The next step is to use sox.exe to make conversions from 22050 Hz (or any other sampling rates) to 44100 Hz. I do no think that MP3 will be a problem, but I need to test that as well. Iti will work only on MP3-capable GPS.