Chords in my songs are automatically converted into blocks but I’d like to see frets instead
There is a known issue where chords might unintentionally look like chord blocks in the preview mode of Yousician right after uploading. These chord blocks should go away after you save the song.
Some of my notes are gone
If your file included multiple voices, some of the voices might get lost during the export to .gp5. The best way to solve this is to make sure that you are working on a single voice while you edit your song in Guitar Pro.
Fret numbers look wrong/weird
If you have originally worked with a standard notation software (e.g., Finale or Sibelius) and then imported that file to Guitar Pro, you need to first make sure that the exercise is in the correct octave. (Since guitar sounds one octave lower than written, you might need to transpose the exercise in Guitar Pro.) Then you might need to workout the fret numbers: Guitar Pro assigns them automatically and they are usually not playable.
When you adjust everything in Guitar Pro, export and upload your song to Yousician normally, and the fret numbers should exactly match in the game.