So I have a decent Mac and installed Parallels to run Windows 10 to play FFXI.

I've got everything installed, and the monitor is 2560 x 1600, and the graphics card is decent.

But for some reason the game won't run past half the above resolution (so it displays as a little box window on my screen). When I hit FFXI play button, it just goes black and cycles back to the playonline login section.

Any ideas how to solve this?