Mini M45/Megasquirt Q'S

The good news is auto tune is going great, I have been steadily building up to using more and more throttle and revs (very restrained for me!!). Afr's are looking good, were very lean.
Issues-

1. The map pressure guage in ts never goes above 90kpa (exactly)?? None of the map above this has been aytotunes also? Should be going higher than this?

2. Earlier when starting there was a pop when ignition on(not yet cranked) and a burning smell. It then started fine.

3 sometimes it starts very very well (more often than not), once it has taken a few cranks, but a couple of other times the stater has stopped cranking whilst for a couple of seconds, then the engine turns slowly then starts, (fooked battery?). The afr's at idle can go from great(13ish) to very lean (16ish). Obviously at cold start, but sometimes while driving and pulled up (again, it's fine more often than not).

What u lot think? The 90kpa thing is worrying me?