Some oddities in Eldritch Wizardry

I have, like I have mentioned both here and elsewhere, started to take a serious stab at write some psionics rules inspired (or cloned) from Eldritch Wizardry.

I already know that my favourite way to do it is not the way it is done in EW. Way to fiddly and too much senseless calculations. I'm not sure I want to clone the mess, trying to make sense of it or just rewrite it my way inspired by the general concepts. But, I want to take a stab at "getting" it as it is.

Now I have a problem. I have been staring at that little booklet, with its very jumbled set of rules, for far too long. I can't seem to find any indication of when Basic and Superior powers are gained. Have I read that somewhere and right now stare straight at the text where it explains how they differ? If you can point me to where in the rules that is, please do!

This reminds me of the last time I tried to make sense of the LBBs. I ended up reading S&W to make sense of it!