I have noticed that there has been a fair amount of discussion concerning the player mats and how easy the pieces are moved and displaced on them. I solved the problem simply by placing a piece of Perspex (glass from an old picture frame would probably work just as well) over the boards, then placing a very small piece of blue tack at the bottom of the resource marker cubes. They can then be easily moved to track resource production but never accidentally slide or move.
A member of my gaming group has glued a piece of plastic which creates trays for the indicator cubes and a kind of cavity for the resource cubes. It's very usefull even if because of the thickness of the plastic you have sometimes to put your eyes right above the track to check your cube is on the right place (I'm not sure I'm very clear ...). I don't know how he created the plastic piece.