12 Valve new engine excessive Carbon Buildup?

Does this look like excessive carbon buildup after 4700 miles on a new engine? It was suggested to me that the carbon is responsible for the marks in the cylinder walls and potentially was flaking off and gettting under the valves causing excessive leak down measurements. 12 valve, P7100 set at 480 cc, compound turbocharged. HX35/S475 171702. Now it has had three sets of injectors during the 4700 miles. Initially the factory 215 hp injectors that were discovered to be leaking, not popping correctly and peeing past the nozzles prior to popping. Then a set of factory bosch VE nozzles (~.009 x 6) that popped and had awesome spray, then a set of DDP Stage 2 Powerjets that also popped and sprayed awesome patterns and made a bit more horsepower than the VE nozzles. The 4700 miles were used to initially break in the motor (easily for 500 miles with the fuel plate at a low setting) then tuning of the P7100 began to calm down the smoke under WOT as the fuel plate was indexed to the 480cc setting.

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12 Valve new engine excessive Carbon Buildup?