The pulley does rest against the 4 screw heads when using the Xenon and RW spur gears.
However, it does not cause any issues. You just leave off the extra shim included in the instruction supplement. In fact it makes you think this was their original intention hence the updated instructions (the instructions do show an interference fit with the screw heads). The Xenon Panaracer style gears are thick as well.
No extra wobble (perpendicular to the chassis) over the Panaracer set-up. I have loads of packs on mine and there are just slight marks from the screw heads.
*Shrug* To each their own! I will take the one less spacer to worry about personally.