EGO correction for dummies: I need it.
 

Can someone please explain to me exactly what each of these areas I've circled does/effects in straightforward terms. I've read here and in the manual what they should be set to under different conditions and have a rough/shallow understanding of what they do but I haven't been able to find clear definitions of what they actually mean. I'd like to really have a firmer grasp so I know how to appropriately make changes rather than just following what "so and so" says they should be.

"Ignition Events or msec per Step" - That's how many cylinders it fires before it takes another step. That is, it makes a change, and then looks at the next 32 ignition events and their cooresponding A/F ratio before making another change. A big number here means it will make slower, more stable changes. A small number means it will react quickly to make changes.

Controller Step Size %- How big of a change it can make to your current VE value.

Controller Authority %- How much of a % EGO can adjust the values in your VE table. You set it to 5% and it can only adjust them up or down 5% of their original value. I give mine 10% authority.

No idea about the one on the right. MS2 here.

So step size is how big of a change it can make each step and authority is the limit to how far those steps can get from the original VE value? Also these are all percentages of VE numbers not AFR numbers, correct?

Yeah that's correct. The change EGO limit field would let you change its authority limit above a certain kPa, 245 kPa in your pic. If you leave it at 0, I believe you're effectively telling it to go to zero authority, which would be open loop (no EGO correction), above 245 kPa. No boost yet myself, but I'm pretty sure everyone runs open loop in boost anyway, and probably at a much lower kPa. It's a safety thing, don't want your wideband to pull fuel under boost if it happens to take a dump and you have EGO correction turned on.

You can set the kPa point above which EGO correction is turned off, in the pull down menu called "open loop mode" under "more settings." I don't know if that would be functionally different than changing the authority to 0 in the lambda sensor targets section. I suppose it would be possible (using the EGO correction settings, lambda sensor targets, and open loop mode) to set up three different levels of EGO correction based on manifold pressure.

yes, under lambda settings I do have it going open loop at 101 kpa.

According to MSnS-Extra Software Manual

If you are using a WideBand Lambda then the AFR Target Table is another option (an 8x8 table), if using the table then the EGO switch point is ignored.

Ignition Events per Step: set this to a value that would switch about 4x a second at your average cruising speed.

4 cylinder assume 3500rpm cruise set Ignition Events per Step to : 29

Thats all for now...back to reading.

I never realized that, i guess it makes sense though. You put in whatever voltage you want ego correction to shoot for, only problem is when you do that you can only run one AFR. Would be fine for a Narrowband