This should be pretty easy to do using a simple adaption of some of the code posted in
this thread about image scaling. It deals with locking focus on a view that you want to draw into and then telling an image to draw itself at a certain location there.
I will try to whip up some sample code for you if nobody else does tonight (I am a bit busy) but the general idea would be:
-load the tiff into an NSImage instance
-lock focus on your game field view
-tell the image to draw itself in the rect (some co-ordinates of where it should go) from the rect (its dimensions) using code similar to that mentioned in the link above
-unlock focus on the game field view
That should do it but I am not sure. Take a look at the other thread to see if you get the idea from there.
Hope that helps,
Jeff.