What I'm wondering is if your O2 signals are getting corrupted. Vac leak, exhaust leak, misfire - those all make it read lean. -32 is maybe the maximum value possible, which implies that the O2 voltage has gone high and the ECM can't cut fuel enough to get the sensor back to 1/2V transitions. Perhaps the sensors aren't grounded well or too much ground is shared with your ignition coils. Maybe there is too much EMI off the ignition system or the there's a missing ground strap.
If your tune is really good, you can practically run without O2 sensors, at least for troubleshooting.
Other than the above things, to go rich for real means bad data or bad math. Where did the base file come from? I think it's possible to have a MAP sensor mismatch. IIRC, even some NA applications got 2 bar sensors. If what you have doesn't match what's in the ECM you could potentially have MAP off by a factor of 2. Again, for troubleshooting you can just unplug it. If it runs better without MAP that's a clue. A broken MAP should be obvious with your little scanner. Vac should be high and dip quickly anytime you blip the throttle, then go right back.
