Thanks @doug293cz for clarifying, I had it all wrong!At 42° and 11 psi your carb level at equilibrium will only be about 2.24-2.25 volumes. This may be on the low side for the style.
Also, did you purge the headspace in the keg of air (multiple pressurize and vent cycles) after you filled the keg? If not then the CO2 partial pressure is less than needed because some of the headspace pressure is coming from air. You also need to purge the keg to get rid of O2 in the headspace to prevent the beer from oxidizing. This is especially critical for hoppy beers.
Jayjay's advice about overfilling slowing down carbonation rate is also correct. But, colder beer does not absorb CO2 faster, it absorbs more CO2, at a slower rate, than warmer beer.
Brew on
I wouldn't burst carb at overpressure at this point. You are at an unknown carb level, and using overpressure risks over carbonation. The overpressure methods work best when you know your starting carb level, and you know the time, temp, pressure parameters that won't push things too far.
Yes, to use the carbonation lid, you have to swap the standard lid for the special lid.
No... Just move the gas connection to the regular one on the keg. If you only have one keg on tap at a time, and have time enough between when one kicks and when you want to serve another to take the carbonation process into account, then you'll be good.
