A close up picture of the cheek block really doesn't help.... perhaps an overall shot showing how the sheets actually behave. You can probably solve the problem by rotating the blocks so the closed end is oriented toward the outside. like this:
You can also replace the open type you have now with closed organizers.
There is a trick old Nacra (beach cat) sailors used to keep the sheet from fouling in the rotating mast step... we tied a length of bungee cord from one end of the cross beam up to the mast and down to the other end... this "canopy", created by the single, stretchy shock cord, kept the lazy sheet off that area quite nicely while allowing the mast to rotate.