I finally had a similar issue solved after months of changing components one at a time to rule things out and here's how it played:
Initially the misfire began not long after having the AC pump replaced when it decided to seize up and explode - however it soon became apparent that this had nothing to do with it. We thought it could have been a loose pipe or something nudged during the AC replacement, but no, after an hour inspection there was nothing loose at all.
The misfire firstly seemed to be either after the car had been running for an hour or so under normal low power driving - or it'd be there straight from the off regardless of temperature/fuel type/air conditions etc.
It then began to be almost predictable - drive it with no power applied, changing below 3k revs and it would be fine for a 30mins / 1hr but as soon as you stop at and traffic or pull away applying power on even the slightest of hills and it was there.
Finally this occurred with an engine check light flash and then a permanent engine check light. This resulted in it firing on three cylinders and could barely even drive it the last mile home without pulling over, ignition off and starting up again. Fortunately the dealership had seen another TFSI with no mods experience exactly the same issue which helped to rule the re-map out.
Over 5 months this is what was changed:
1) One coil pack changed on the effected cylinder - misfire still present after this.
2) All spark plugs upgraded - misfire still present
3) All coil packs changed - misfire still present
4) Injector 4 replaced (all seals etc too) - misfire gone and driving better than ever.
The CAM and CAM Follower issue hasn't appeared in my car at all, an '06 model TFSI with 30k and a remap for the last 20k of those.
I must have read 1,000s of posts and threads dedicated to this misfiring issue across the VAG group with the 2.0 TFSI engine, spoke to three different tuning houses using three different remap brands and had the suggestion of upgrading the fuel pump numerous times from different tuners. DanGB provided advice which was well appreciated to help rule things out.
Based on my experience alone there are different components that may fire up similar fault codes although that doesn't necessarily mean that the "normal" component that fails with be the culprit.
There's been wiring looms changed, multiple coil pack changes, fuel pump changes, CAM Follower replacement, fuel pump upgrades etc...and even still there are cars with all those changes that may bring a misfire to the table. After reading so much over the last few months one thing applies regardless - ignition should be as simple as: Fuel Pump, Injectors, Coil Pack, Spark Plug and anything else your TFSI wishes to throw out of its pram!
Besides my absurd rant - i also have CC Phase 1 and i'd bet my badger it isn't caused by the map directly but because under mapped conditions the engine is being asked to do more which is why it's more apparent. If you've had a twintercooler since your map maybe it needs to be tweaked to take advantage of the significantly lowered charge temps?
