The Bank's 'responsibility' would have been the financial commitment under 'performance bonds' which are usually carefully phrased. They probably analysed these carefully when deciding whether they should 'pull the plug' and it may have been a factor in deciding to allow them to trade on and complete contracts which had performacne bonds attached.
More shares bought than sold? surely ewvery buyer has a seller and vice versa ;-)
the trades on advfn are a 'guess' on the initiator's intentions, based upon whether the trade is closer t omarket maker's buy or sell price. There is nothing to stop a market maker reporting a trade later in a day, when it looks closer to the other side. This could happen accidently when a high volume of trades occurs. THey are to busy to record trades immediately, so a sale at 30p shows as a sell at the same price when the price has moved up between the time of purchase and the time reported. IGNORE BUY/SELL DATA IMO