I wanted to know how to create a working one because none of the saves that I create work if you'd bother to read my post and indeed the thread title
Are you aware of the problem of lastsave data overwriting newly added .sav file if you're not careful, as I explained in your GBA roms thread?
Do you understand how to avoid it?
At what point in the game are you trying to edit your .sav. Editing stuff too early in the game can cause errors, I strongly suggest waiting until after Dawn (or the guy if you're playing a girl), gives you 5 pokeballs and gives you a
tutorial on catching pokemon.
I had no trouble using pokesav with the USA release of both pearl and diamond, on a dslinker, also an n-card clone.