Help needed for 2-stroke tuning - 2001 KTM 200 EXC

I bought a 2001 KTM 200 EXC that wasn't running due to a cracked cylinder.  I ended up completely rebuilding it from the ground up.  It is all back together now, but I have no idea how to tune a 2-stroke.  It was completely stock and the carb was stock with the carb set-up as listed below.  But since I never heard it run, I have no idea how good it was running.

 

Current set-up:

   - 212cc big bore kit

   - powervalve & head porting

   - FMF Gnarly & Turbine exhaust

   - Stock carb (180 MJ, 42 PJ, NOZG)

   - 93 octane

   - 2,000' altitude

 

I set it up as:  180 main, 42 pilot 1 1/2 turns, and NOZG 3rd.  It started right up, but I had to turn the idle screw in almost all the way to get it to keep running, and the idle mixture didn't seem to make any difference until I screwed it in almost all the way - maybe 1/4 turn from bottoming out and then the idle started to decrease. A short test run had it running really flat after 1/2 throttle. Then readjusted the powervalve so that it opened a little later. Another test hop and it was a little better, but still flat from 1/2 on - never really revving out.

A couple of things I noticed:
1. There is an occasional popping on decel - kinda like a quiet back-fire or single cackles. On my 4-stroke, I would take that as an indication of possibly being too lean. Is it the same with a 2-stroke?
2. As I was trying to run the gas out of the carb bowl, (fuel turned off, running) once it started to run out of gas, the idle picked way up. Would this mean that I'm running too rich in the idle circuit?

I also had been running a mix of 32:1 for initial break-in. I've since changed to 40:1 but haven't had a chance to see if it makes any difference.

And, finally, I have an assortment of jets and needles now to work with: 170 through 190 MJ, 38 through 55 PJ, NOZF, NOZG, NOZH.

Any suggestions on where to go from here?

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