What graphics card do you have? I suggest trying your native screen resolution first. If that doesn't help, try forcing a different SDL Video driver using Launch.exe. There are two modes, directx and windib. One of them should hopefully solve the problem. If that doesn't help, check to see if you're using the very latest graphics drivers.
If you change the screen resolution on Windows, do experience the same problem? Are you using a VGA cable? Check your monitor settings to see if there is an option to perform an automatic screen alignment.
I've played KeeperFX on many different hardware configurations, and never had an issue with the screen being cut off. That's a peculiar one for sure. Do other games work fine for you?
I've got an ATI Radeon HD 5700.
I run the game in my native resolution (1440x900). Tried both video drivers, no change. Graphic drivers are up to date.
Changing the resolution on Windows doesn't make a difference, nor does my screen perform any kind of automatic alignment.
Mind you, like I said, the game interface is fine. I can select all the buildings and spells, even the Sell button shows up nice and the message markers align up perfectly (with the question mark at the bottom).
However, when I want to open a message ("Your lair is full" or the mission description) it looks as if it opens below the screen, I can just see the top line of the message image. Also, the Map screen cuts off the bottom third of the map.
The sizing problem with the menu I was able to fix (Settings in the launcher allowed me to do that, though with the new resolution, the 'window' overlay on the world map blocks the second world) but the issue with messages appearing just below the screen and the level map getting cut off persist no matter what graphic option I change or resolution I switch to.
So I'm kind of at a loss here.