I've tried to download this demo and it hasn't been working for me, I'm not sure if its just me but the downloads haven't been working.
make sure you get the right version, there should be a 64 and 32 bit version so check your operating system!
also you have to make sure to extract the files from the zip for them to work! make a new folder and then drag everything in the zip into it and it should run.
they dont currently work on mac or apple devices.
if those arent the issues youre having, im afraid im not sure what it could be x_x