Corrected entry: The Kazon man says he is putting together a dodecahedron on the table; however, dodecahedrons are a 3-D shape, and cannot lay flat on the table.
Corrected entry: Voyager has been traveling home for months on a long trip home presumably at high warp most of the time. However in this episode every kazon first maje is able to catch up to them in a short time frame.
Correction: Voyager is not able to maintain high warp speeds indefinitely, as this would cause damage to the engines. Plus the ship will need to resupply fuel and food etc periodically which obviously can't be done at warp. And, as Chakotay's hologram once commented, Janeway has a tendency to "investigate every insignificant anomaly [they] come across", further delaying the journey home and reducing their average travelling speeds.
Correction: This is probably why he can't figure out how to make it.