When Inidu and Enog are standing over the trick hat, right before Inidu reveals the duck there is the film cut visible where the animal is put under the hat.
When Inidu retrieves the rope that had been the snake it appears to be no longer than a yard long. But then Enog uses it to tie him to the chair and the rope would have had to have been much longer than that to tie him up.
When Valerie made howling noises in attempt to scare Enog away he could hear her. But when Valerie is frightened by the snake and screams, Enog didn't seem to hear her.