My opinion, and I stress my opinion only, is this gap and low volume is the result the reaction between the fact that this stock is extremely tightly held and the fact that it is also a long way under the radar of most investors.
My guess is that the majority of current buyers are actually existing holders who have already gotten their fill, but will not say no to any opportunity to top up well below the true intrinsic value of this stock.
On the flip side, existing holders are not prepared to let go of any stock unless they have to and will then have no choice but to sell to the piranhas waiting down below to get the stock at a steal.
Most recent transactions seem to be purchases of loose stock only. If someone wants to get a decent fill at the moment they will either have to pay more, or to be very very patient. However with the trading halt and meeting of shareholders only 3 weeks away, opportunities to get a decent fill will probably start drying up very soon.
Also greater interest generated from the upcoming roadshows will also add to the upward price pressure, and will eventually lead to closing of the gap between buyers and sellers, as Alcidion comes onto the radar of more investors.