It was only a tech demo, hence there being no buildings that could be entered, npcs, menu etc.
He has created basically all the maps for the game, but only wanted to show the two most original areas. The Grungewater Town, as i say, took over 500 switches just to create (it took a long old time) so it was the main part of the demo. I take it you didn't read the instructions on the demo page which explained in detail how to use the tools such as the Axe and Hose..that's a pity really.
He's been working on the Pokedex and menu since, but just wanted to get out a small tech demo for now showing Grungewater.
Both areas are uninhabited because that's the point really -Grungewater is a deserted town you rebuild and then sell on to people once complete, and Fossil Island is a prehistoric land you can explore.
For the past couple of weeks he's worked really hard, and as i've said Grungewater took a lot (and i mean a lot) of work to complete. It's a shame that you didn't read the instructions and play Grungewater as it should have been played.
Bugs, I understand since even he knows there were some ones he didn't work out, but it's harsh to attack on the basis of there 'not being much to show' considering you didn't play the demo to it's full capabilities, and considering that he's completed all the maps and a lot of coding etc. but only wanted to show Grungewater for now for the sake of originality.