The stairs/ladder Plumpick uses to climb to the top of the blockhouse appear out of nowhere.
When the inmates return to the asylum at the end, they leave all manner of attire strewn around the entrance (umbrellas, wraps, etc.). Shortly afterward, as troops march by, those items are all gone.
When Plumpick is trapped in the wires and hits his head, he is tangled. When he wakes up, he is free of the wires, the posture of his body has changed, and his location in the street has changed.
After standing up, Plumpick sees the bear. He then starts to run down the alleyway. His position in the street changes from when he stands to when he begins running.
When soldiers put Plumpick on the piano, both legs are on, but when he is taken off, one leg is hanging off.