I worked on the MS440 for a few hours last night.
Cylinder: After looking at it closer, most of what I initially thought were burrs, was just light reflecting off of chamfered edges around the port openings. I touched up one of them with my Dremel but left the rest alone.
I spent about 30 minutes at the bench grinder grinding down the shaft diameter one a stihl wrench/torx combo tool so that it would be narrow enough to fit through the cylinder holes to tighten the cylinder bolts.
Base gasket: My kit included two pieces of base gasket. Both identical, metal. They measured about .014" thickness each. I only installed one, using three-bond 1184 on it also.
Got the cylinder installed and everything looks good there.
Oiler: The oiler pump/assembly piece has two bolts that hold it in place. While tightening, the bottom bolt started to strip out on me =( I got the top bolt tightened well, and gently put as much tension on the bottom one as I felt comfortable with to prevent completely stripping it out. I'm hoping this doesn't cause problems later. It feels like the oiler assembly is secured well.
Chain tensioner assembly: In other assembly videos online the gear piece with a screwdriver slot is a silver/brass part. Mine was black, and would not fit. It was too big. I compared with the ms660 kit that I have, and it was an exact match. I believe my 440 kit was shipped with the 660 chain tensioner. And unfortunately it doesn't fit. I tried to modify it to work, but that didn't work either. I will contact huztl about this and get replacement parts.
Muffler: muffler install went well. However the kit does not include heat reflector tape for under the muffler. I plan to order something to help with heat under there.
Flywheel: Flywheel installed easy. I didn't mess with changing timing on the flywheel key.
AV mounts: I wiped a little bit of 10W30 motor oil on the rubber mounts before pressing them in by hand and this helped a LOT. There is one small AV rubber piece that goes just below the coil that was still difficult. I tried the string method, and it popped in on my first try with using both string and a little bit of oil.