Need some help with LSJ tuning.

Car is a 2006 Cobalt SS/SC on 93 pump gas

Mods are:

3 inch intake
LS4 tb
TVS 2.8 pulley
80# injectors
OTTP Return Style kit with base pressure set to 42lbs at idle with vac line hooked up
7GPH meth nozzle 50/50 mix

Problems are:

My tuner told me all that was needed to change when I installed the RSFS was the IFR vs KPA vac chart to 57.8 across the board. I did this and sent him the log and he said, everything looks good. But things are far from good. My car will hold around 2000rpms when I put it into neutral going down the road and the afr stays around 11.5-12. If I slow to a stop it will settle out and idle fine. It only acts up if I put it into neutral. You can see some of this in the data log I posted. I have given up on that tuner and now would like some help getting my car dialed in myself. Can someone please look at the files and tell me where to begin.

in the return style fuel system you set the pressure to a common base psi. if you can match it to a multiplier kpa vacuum value the better off you will be since you can select that column and paste it into the entire graph. its been a really long time since i have touched the lsj ecu but starting with the correct base pressure to match the kpa vac table will help you out a ton. measure your base pressure with the vacuum line disconnected. base pressure is measured without any vacuum corrections just straight mechanical return pressure.