Alright so its looks like my best option is to learn the program with 2.57 and following along with the guide and then just using the latest NIF script supported version of Blender which i think is 2.49b, now my second question is am I going to cause any irreparable damage attempting to keep two versions installed?
well... imho it depends on what tutorials/books you're following. since the difference in UI is so vastly different, i'd stick to one version or another. i'd recommend learning 2.5x since that will of course be the standard moving forward. if you're using it for FO3 (or similar game), you can do your modeling in 2.5x, then open up your model in 2.49 and export from there. keep in mind if you do any animations, they will not port from 2.5x -> 2.49. you should be okay the other way around though (haven't tried it myself, ymmv).
i actually use both versions myself. for me personally, i install 2.49b using the .exe (i'm assuming you're using windows) -- that way all the registry entries are there for that. after i install 2.49, i download the .zip version of 2.5, which does not need any install. that way (i think) there are no possible conflicts with respect to the NIF import/export scripts. just
make sure you get the proper versions of python and pyffi so the script installer is happy.
thanks for the vote of confidence, andy. :foodndrink: