This design sets the roll back from the edge of the table to allow you to use the full length of your table surface.
I recommend leaving a bit of space on the side of your roll to allow for side-to-side adjustments while you're pulling and setting your transfer tape.
I'd also recommend using some stronger "C-Clamps" rather than the cheap ratcheting clamps shown in the photos.
Designed to be assembled with 2-part epoxy and (#6) 2in drywall screws. If you have trouble inserting the screws, drill out the holes slightly larger, but still allow for some material for the screw threads to "bite" into the plastic. 
Most 2-part epoxies (even the "5-minute" epoxies) recommend letting them cure for 24 hours for full strength.

Recommended Print Settings:

Nozzle Size: 0.4mm
Layer Height: 0.28mm
Wall Count: 4
Bottom Layers: 4-5
Top Layers: 4-5
Infill: 10%+
Print with brim