Watching this video, it appears that the hydraulic ram intrudes into the cargo space and would run into the Unit Load Device (ULD) that was stowed there.
Is there a special ULD that is loaded on each flight to clear the ram, or is there enough clearance that any ULD will fit in this spot?
No, the container near the door is the same as the others. The containers do not fill the entire cabin all the way around, which leaves enough space above for things like the door hydraulics. The containers on the upper cargo area below are all 88" x 125", which corresponds to a standard LD7 container.
