Barbara - The thing that you have overlooked and I must admit that I did also - is the piano. If it is playable - it remains an Entertainment Facility and licensable.

However, I tend to agree that in order to be considered as Regulated Entertainment it has to be - for the purpose or purposes which include the purpose of entertaining even one spectator. And that social musical gatherings like this (or perhaps without a piano) are not for that purpose and would take place in the complete absence of any spectators.