One way to discuss such publications is first to ask a JW how they envision the GB getting truth from Jehovah with which to feed the sheep.
After all, they are His channel of communication, right?
They will probably say that the GB members pray earnestly for guidance and diligently study the scriptures.
Establish that these brothers take their responsibilities as the FDS very seriously and carefully screen whatever the organization publishes as truth in Jehovah's name.
With that picture in mind, then have them read aloud some of the nonsense in the materials you've selected:
-- Pyramid measurements "proving" that Jesus returned in 1874
-- Leviathan being the locomotive
-- Distances in Revelation being the distance between Scranton, Pa. and Bethel by way of the Hoboken ferry
-- Michael the archangel being the Pope of Rome
If that isn't sufficient to make the point, ask them what Jehovah and Jesus thought when they saw this spiritual food coming off the presses, being taught as truth from Jehovah's table.
Ask them how quickly they think Jehovah and Jesus acted to correct the errors and give the GB new light.
Ask whether they believe Jehovah wanted the readers to accept all that as truth until such time as the GB decided to publish corrections.