Most of the time I print on my Kelsey I manage to get the impression right pretty quick but trying to print my new plate for the back of my cards proved to be a right pain! I had the plate landscape then portrait just to check it if it needed any make ready tissue on the back as it kept missing ever so slightly in one corner, changed my packing, but no it wasn't that, just hadn't got my impression screws just right, when all else fails and it still won't print right, take a break, back off the impressions screws and start again, you'll get there in the end :)
There's a problem with the Kelsey Excelsior when you start on a long print run, after a while the impression screws will just slightly move, messing up the impression, common problem I believe and some people have resorted to replacing the screws at the back with bolts and washers!
