Pokemon bw2 rom changer error/ no Encounter

[simon99s]

After first successfully using bw2 rom changer on black 2 to change stats, evolutions, and encounter, suddenly when I play the game there is no encounter at all on newer routes(routes which encounters I changed recently), but still the encounter I changed to on earlier routes. Now, if I try to open the rom on bw2 rom changer an error appears right after I click on one pokemon.

System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.

bei POKEMON_BW2.Form1.WriteData(Int32 index)

bei POKEMON_BW2.Form1.listBox1_SelectedIndexChanged(Object sender, EventArgs e)

The rom changer still works for the unedited rom.

I also changed the narc files for trdata, trpoke and changed the text(a/0/0/3) to a text from another b2 rom with different starters, so the text will show the starters lol. Does someone knows how to get the rom to work on the rom changer again, what is the problem??