no lyrics on first mp3

The UNSYNCEDLYRICS field is not for karaoke.
Check if you have a language token in front of the lyrics, e.g.
eng||It's been a hard day's night

You then have to check which languages can be displayed by your player - sometimes they only accept lyrics in the language of the OS language (in my case "deu").
You then best replace the "eng||" with "xxx||".

Also, could you explain what you mean by

What do you convert? Unless you want to do something with external data, no conversion is required.

If you want to get aquainted with the basic functions of this program, it is still advisable to consult the help pages and search this forum.