Yeah shaders don't compile correctly on intel integrated cards. I don't have an actual intel workstation card to test on so I don't know if it will work on a non-integrated card, but I suspect it doesn't.
If you look in the console log it looks like the shaders don't even compile, you just get tons of errors. Example:
http://pastebin.com/3WgUv7vqI'm not sure this is a bug though, it could just be that Blockland shaders just aren't compatible with intel cards at the moment.
So if you're stuck playing on a laptop with an intel 3000 hd chipset you're out of luck, no shadows for you.