I'd like to make those alterations to those 2 effects

http://www.youtube.com/watch?v=Cn5RhZodaA8&feature=related 05:55 the "warp effect" on alduin

and the summon dark portal effect

I think the NIF files are:
SummonTargetFX.nif
FXAlduinTimRift.nif

how editable are those? do I require niftools even for something that shoud be simple as resize-change duration or I can do that in the Creation Kit?