Doubt about Shrinking Focus Power

Hi, i am not sure about how to read the Shrinking Power... Do you need all the 25 levels to Shrink freely or only 5 levels are needed to that? I don't get if only if you don't spend all levels an change the Size for those Might Point spended...
RoP Faerie page 60.

Only 5 levels, by my reading.

Sorry, I just can't make sense of the sentence above...

MuCo5 Shrink
(base 3, pers, +2 sun, ind)

So you have 20 power points left, or 4 points to reduce Might cost or improve Initiative. I don't remember if this is spelled out here or only in RoP:M.

Now, if you are Size+2 or want to shrink something else than yourself...

I don't know if this answers your question or not, though.

First thank.
But...

Focus Powers Intrincacy points can't be spend to reduce the Cost.

I remade the question: The 1 point/ 1 times you can change the size... Is it you maintain the 25 levels on the Powers? O included if you only take the 5 levels?