A.I.R and IR3

[Staticwave]

Hey guys, i just got my first angel and it came with angel air so i just got a few questtion about it.
First off when i turn it(air) on its says lo-p, and i believe ir3s are high pressure so how would i go about changing it to high pressure? and does it nedd to be filled first? bc the tank is empty.
2nd, for filling should the pressure/velocity screw be in so its flush with the reg or sticking out? and if after i fill it if i keep at least 1000psi in it will that help prevent flash fill or does it not make a difference.
and there is a small screw right above the in port what is that for?

thx for any help u guys have and any other suggestions or comments would be great.

[Crazy Train]

Lo-p means that it's the pressure leaving the reg and into the gun is below 100psi or basically OFF. You need to turn on the airflow by screwing the screw in the front of the reg inwards to your desired pressure by watching the output pressure reading on the LCD. You can fill it while the tank is on no problems but make sure it's filled slowly. A flash fill can easily damage the main seal and you will need to replace and/or rebuild the seals in the reg.