When Pearl goes to say goodbye to Walker in his garden, there's a shot of him, and his jacket is on the fence. But in the next shot, she's carrying the jacket, and she's the one who puts it on the fence.
During the scene where people are watching the moon landing, the TV image shows the Moon's surface taken from the LEM as it descends and lands. This video was not available for viewing until after the astronauts returned to Earth.
On July 20, 1969, the moon was only 6 days old - roughly a half moon as viewed from the film's location - and would have set by 11 pm, but on the night of the moon landing, they show a full moon, high in the sky.
In the Woodstock scene where we see Pearl and Walker standing together there's the announcement, "Good morning! What we had in mind is breakfast in bed for 400,000" and Richie Havens is singing his "on the spot" improvised song, "Freedom" which was actually the last song after his very long (almost three hours playing) musical set as he opened the festival on Friday at 5PM. The breakfast announcement was made by 'comic' Wavy Gravy on Sunday morning describing the "granola" gruel that was created/invented to feed (as many as possible) the 400K attendees at the festival.