Hi there. First you should make sure that your file is set to public, that is widely open to anyone on the internet. Just right click on your file, look for the share settings and tick "public on the web". Then grab the file public address and replace the "open" part of your file's with "uc".
For example, once I was able to hotlink and image stored in google drive, with the url being: https://drive.google.com/uc?export=download&id=0B6qfZTTjzGKqVkt5VXRfazV5SzA
Note the "uc" part in the url.