Fireworks does not support high resolution retina screen such as the one as you are using. Since the development of Fireworks was halted in May 2015, no updates or bug fixes will be released to fix this problem.
The only possible fix is described here:
Or reduce the resolution by half on your screen when you wish to work with Fireworks. Or connect a second non-retina screen to your computer, and use Fireworks on that screen.
I think it is an odd situation that Fireworks is still officially part of Adobe CC while retina screens on Windows remain unsupported.
Thanks very much it works very good.