Danny and luke should post up their ignition map
and mike if I came across and engine of this spec that couldn't make decent boost at 4500 rpm I would be checking the rpm scaling of the rollers the data log and then the engine to rectify the issue
The sudden loss of 2 bar of fuel pressure will just cause the engine to cut and will cause no real damage for that short term
continued use on boost as you did is well to be polite foolish
you have now given danny some ignition figures to check against lukes map did Harvey give you them you now need to give him the next rpm break point timing values