You may use WeiDU to extract 2DA files (or any other type of files) from biffs if you like.
weidu --biff-get kitlist.2da
Or optionally:
mkdir myfiles
weidu --biff-get .*2da --out myfiles
The former will get that single 2da file, the latter will extract all 2da files into the folder "myfiles".
However, having NI or InfExp around will make it easier when it comes time to actually make the kit powers.
I'm of the opinion that if you present a well thought set of instructions, you can lead even the newest of the new to a happy ending. Simply take a look at the other kit tutorial offered on that page and you'll see what I mean.
I'm afraid that I haven't seen either of these kit tutorials (that includes the WeiDU one).
Even if you give a clear set of instructions, some practice is required. For example, you could give me a very clear set of instructions on how to shoot free-throws in basketball, but I still won't make them consistently or be successful the first time after merely reading the instructions.
I did use "winbiff" lastnigt to extract those particular "2da" files and I also downloaded the "IEEP" program, and am now curious since you mentioned the "NI" program as to which is better suited to newbs and is there any night and day difference between the two as to what they can do?
IEEP is a better tool for beginners. It presents a friendlier interface to editing ITM and SPL files.
NI allows you to view and edit basically any Infinity Engine resource. It can extract files from biffs, change ITMs, SPLs, CREs, 2DAs, compile and decompile scripts, etc. However, it assumes that you already know what is going on. It is much more convenient for mod-making if you are already familiar with IE editing. I cut my teeth on InfExp and IEEP and then moved to NI when I wanted more speed and more flexibility.