Keeley said:
i'll probbably answer this myself but doesn't the DSTT save Platimum as 1mb saves and PokeSAV supports 512mb i thought unless they changed it
Sorry, I know it was probably unintentional, but I chuckl'd.
Anyway, yes, pokesav works fine with saves from the DSTT. The only problem (if you can call it that) is that you'll need 2 different versions of pokesav; one for Platinum saves, and one for Diamond and Pearl saves, but, as I said, it's not exactly a big deal.
Although, if you don't know how to use pokesav in the first place, well... I can't really help with that. Search youtube, I think there was some tutorials on there, if memory serves me. Or, better yet, make a backup of your save, and just mess around, see what happens. Try to make a legit-looking pokemon, for instance, or even try to make a shiny magikarp called George roam Sinnoh. All it takes is a bit of experimentation, and you'll eventually work it out.