Yes. This type of engine, when new especially, is VERY tight near the top of the cylinder (TDC). This will loosen up slightly as the engine breaks in. The loosening is part of what will eventually allow a slower reliable idle. This tight fit is also where some of the "coloring" you are seeing is coming from. The engines are machined to such tight tolerances these days on the CNC machines where they are made that they need to break in and "wear in" to a final fit.

I would not loosen the head screws (I'm assuming those are the ones you loosened, as you did not say). If you don't get the head back on perfectly straight and torque the head screws evenly, it is possible to distort the parts or cause a leak. I hope you are not moving the sleeve also while the head is loose