It has ???? marks all over the place. To figure out which buttons you need to press to make it work, download the DP (yes you heard me Diamond Pearl) POKESAV and open that to figure out which buttons to press to make what work. To modify pokemon, I would open the save with the DP pokesav, first, save the PKM file (after modding moves etc.) of your party pokemon and then open the save file with HGSS load PKMs into the Party slots. Bingo! Efficient way to deal with your Pokemon WITHOUT dealing with giberrish.
Make sure you change your trainer/pokemon names with either Pokesav first and Make sure that original trainer name, OT gender, OT IDs (secret+regular) match.