If the compressions were down (say equally- very unlikely) then it would struggle to start from cold without alot of glowing and white smoke. I dont think compressions are your problem.
Couple more things to check:
It would seem to me that something is preventing it getting full fuelling. Are you certain the ecu is seeing a good load signal from the maf?? You want a good 4v at about 2500rpm upwards.
Has the wastegate actuator rod fallen off, or the poppet valve inside the housing melted/ fell off, or something is jamming it open. Get a boost gauge on it - you should see 10-12psi at full load, 2500rpm, which will fall back to under 10psi as you approach 4000rpm. I've also seen actuator rods unwind themselves when the locknut has come loose. Check the yellow paint is un-disturbed.
Sorry for the random musings, but it's been a long day!!!