I really enjoyed this demo, especially the graphics and the game design. So I hope my comments will not sound too negative :)
In addition to what @MadRobotGames said, I think the ennemies are sometimes too powerful and thus the death rate can be very high. This is a bit frustrating. For example I died 4 times just to cross one section of the map because my HPs where too low to manage to survive that much combats.
To overcome this I think there should be a way to regain HPs faster between combats and/or the option to flee during combat (at the expense of HPs or inventory items for instance).
Not really an issue, but it could also be great not to have to choose which ennemy to attack when there is only one left.
Nevertheless, I can't wait to test the next updates of this game :)