What I found it's not a bug (I think), but might be useful for someone:
When you transfer a Pokémon from Colosseum to GBA (in this case, japanese Scizor) using this tool, the Trash Bytes in the name are filled with FF's instead of 00's. Here are some pictures of what I mean:
Trigger's PC
An emulated transfer with Dolphin + VBA
Both are exactly the same Pokémon, but migrated to GBA using two different methods.