That does look odd. Parts of the file will get cut into sections in the transfer but it is usually not visible to the eye, you have to select an object to see the lines and points. My guess is that it is just an effect of the screen and won't show up when printed, although I doubt if you want to risk it. Try enlarging the view and see if it disappears.
Best thing is to follow Peirs' instructions for making the postcript file then creating a Distiller file. Distiller files are what printers usually ask for these days, in fact some will accept nothing else. Get specs from your printer on what settings you need.
The only thing I question is Peirs' saying to set the lpi at 175, seems a bit fine for a local printer probably using paper plates for a small run, but it's best not to guess and ask the printer what he wants.
And stop using Freehand and take up Illustrator. There was a time when I wouldn't touch Adobe and would only use Freehand, it was by far the better product. Now, though, I use Illustrator exclusively and haven't opened Freehand in months. It hasn't kept up while Illustrator has, and so few people have Freehand now it's too much of a hassle to use it at all.