Does lower resist make psn Nova take more dmg ? Any idé what Lvl if it make diffrent ?

Any one who know somthing about this ?

yes lower resist curse helps with poison resist.
paladin conviction, however, does not.

Yea it does. Including skills from gear I wouldnt bother getting more than 15pts in it or wherever it hits -60% res. After that it starts taking way too many pts for such a small % difference. Like level 30 is only -65%. With basic gear youll probably only need like 2-3 hard pts in it