First of all, congratulations for getting this event off the ground, I imagine there is a lot of organisation and planning involved in setting this up and no doubt to make the event work the figures need to be right. I also think it's a great way to introduce the concept of craft brewing and homebrewing to a wider audience.
Without being negative about the festival as a whole I have to agree with RichieH on the entry fee for the brewers; it does seem a bit cheeky to ask brewers to bring 20 litres of beer and pay €40 for the privilege, even taking the entertainment and food into account.