The flat where Violet and Fred live now has a spare bedroom, but earlier in the series, Fred had to sleep on the sofa when Violet's back went out. It's possible they converted a room into a spare bedroom because they realized how practical it would be, especially if one of Fred's daughters came to visit, but this was not explained.
The headline ('Glasshouse Village Trust Celebrates It's Second Birthday') in the newspaper mock-up that Shelagh opens at 0:44:38 contains a grammatical error: the word 'it's' (a contraction meaning 'it is') is used instead of the intended possessive pronoun 'its'.
When Ivy Jackson collapses into the aisle at church, she makes such a noise that the other parishioners stop singing. Barbara is already at Ivy's side when she calls for Tom, yet when the camera cuts to him he is still walking away from his pulpit and only just turning around. He would have noticed the disruption immediately.