Idle is controlled by the PCM. Sounds like they want you to crack the throttle plate slightly(?) - bad idea. At idle, the O2 volts should oscillate around .45. If it isn't, the PCM will keep trying to lean out the mixture to get it to do that.
I have the S-AFC so I can't really help with setting the Pro Flow. I know I had to set my 1000 RPM point to +6% to keep the engine from stalling, but only when the RPMs were dropping to idle. Never had a problem sitting at idle once it got there.
