Hi,
I tried the game and had no problems with the controls. I'm on Ubuntu + Firefox. With that out of the way, I would say it took me several tries to 'get the game'. It was unclear to me how to control the game. This is in part due to the long time that it takes between pointing and the actual shoot. To me it feels unresponsive and leads me to click again, canceling the previous command and starting again the whole process. Also I would like to point that the action of taking a hostage is a bit unclear, I didn't get it with the icon you've used. And I don't know if it's meant to be like that but once I got a hostage I couldn't fire to someone behind me and I had to release the hostage to be able to shoot and it feels quite counterintuitive.
With this said I think it's a cool idea and with some refinement of the controls and the responsiveness of the character you might be up to something cool. I hope this helps :)