Provided that the ECU SST torque tables are correct then you shouldn't see slip with the correct version of the SST firmware as it should calculate the required pressure based on the torque demand from the ECU. Certainly if your box is slipping with stage 1 power you've probably got other issues with the SST unit itself or the map in the ECU.
If you weren't able to do the teach-in chances are you have a 2008 SST unit as I believe all the 2009 firmwares allow teach-in by default.
Mitsu patched the cold start out of all firmwares in 2014 (or earlier) as per my earlier post so provided you have the latest version of each of them then you won't get the mechanical start up noise on any of them (see the TSB here
). You were only getting them as your car was still on the original firmware for the 2008 SST unit rather than the updated 2008 version they have available now.
The increased pressure you are seeing is an example of what I mentioned earlier in the thread (i.e. the 2011+ SST has a different physical design than the 2008 unit) and it's not necessarily a good thing. For example if the pressure is consistently higher then it may cause clutch dragging, side effects with the mechatronic operation or simply rob the engine of power for no benefit.