Well Google is at it again phasing out plugins which has caused the GUNSTRUCTION player to break on Chrome. If you log in and see a screen like this you will need to do the following fix.
Open a new tab and type in :
chrome://flags into the browser search bar
You will see a bunch of various plugins you can enable/disable. The best way to find what you need is just to do a search "ctrl+f" and look for "npapi". You will see it here:
Go ahead and enable it. It will then turn one and look like this:
Lastly at the bottom you can restart Chrome, or just close and reopen the browser.
We will be looking into a better solution for implementing GUNSTRUCTION as Chrome continues to make using the Unity Player more and more difficult. Y0u can always just use firefox if you don't want to deal with Chrome.