Ok, finally figured out. I think the problem was I was editing the wrong file.
One problem I have left is that the seats in the pko tables seem to be a couple of pixels down from the ones at the regular table. However there is a PkoTableConfigOverrides.cxm file in which I think you can adjust seat positioning just for the PKO tables. Hopefully, this will solve the problem.
Last but not least, Prolix, you ve said that the graphics are distorted for some reason. Here's the reason and how you can fix it.
When you set coordinates for an element, say 0,0,100, 100 what you re doing is assigning an area 100 pixels wide and a 100 pixels tall to that element. The image you put in that area should have the same proportion. If you try to put a 150 by 100px picture in that area, 888 software will squeeze the picture horizontally in order to make it fit.
Btw, this is how you make the graphics better. If you try to put a 200 by 200px picture in that area, 888 will fit it in in the right proportions, but since it's higher resolution, it will look better.