Wierd King's Indian Game

So I'm trying to analyze this game and I have a few questions that I can't answer for myself.

First -- what is the "right" response to white's Nge2-g3 manouver.

Second -- is my idea after Nf5, particularly sacing the knight on move 18 -- a viable idea or am I actually losing here?  Is the initative worth a piece?

Third, I can't seem to figure out what happens if 27. Rb1 instead of 27. Rd1. I think white might hold out at that point, but can I keep the pressure on? I'm not sure.

Thanks!

Phren thanks for the response.

Do you have a recommendation for a good KID text?

The extent of my study of this opening has been a couple of videos and an essay on the Mar Del Plata variation.

Thanks!