.NIF importing and exporting addon

Hi, I need a updated NIF addon as I cannot get the current NIF addon to work either with 2.49 or 2.78. I do follow the instructions to the book and my Fallout/Skyrim folders is set correctly, but I still get errors and I have spendt the last few days researching the problem. What I want is a updated NIF importer-exporter for modding use in Fallout/Skyrim.

Is there any experienced programmer than can do that?

Regards
Aasmund Schei

Solved, found a working NIF plugin for 3Ds Max.