The game has good concept, but it seems a bit broke. For example, I'm falling through the world and my pickaxe can break anything without a problem. I'm not saying it's the worst game ever, but I'm sure you're trying your hardest to get the bugs fixed.
Overall, I'll give it 3/5 stars. You did make a good clone of Minecraft, but has many bugs to be fixed in the process. I'd love to see this complete someday. Thanks!