This is why having two monitors is awesome.
Oh, and no, you can't find the magical offsets to change weapons - it's a little more complex than that. He actually took the hex that you look at in the EXE and converted it to machine code, which is in essence a type of programming language (*The* language, in fact, that all programming languages are compiled into).
In all probability he had to either make the area of the code handling weapons bigger or smaller than it originally was, meaning your offsets will be meaningless. Furthermore, in order to do anything other than exactly copy what his weapons do, you will need to learn machine code. He didn't just change some offsets which loaded different effects, he coded the effects himself via machine code.
Offsets are not magical little numbers which can be changed on a whim, they're simply the location of values that may make existing code act differently. Runelancer didn't find the special offsets for weapons and change them, he wrote his own code for the weapons. If you really want to change weapons, or make a quality mod that is as unique as Original Sin, you're going to have to suck it up and learn assembly.