I have had my Janome 6500 since May 2004 and I have always had the issues you described. The bed of my machine does have worn off paint and missing paint in a couple of places. The paint has also worn off around the edge where the acrylic surround sits. This machine has always liked to chew up fabric at the start and veers off the seam line at seam junctions. The bobbin case will also knock, rattle and jump out of place if that oil wick under the bobbin case dries out (they don't tell you that in the manual!). I have had a love/hate relationship with this machine since I bought it. I know other owners sing its praises but in my opinion it does have some issues. Good luck resolving this with your dealer.