Atom Zombie Smasher seems to be getting framerate problems on some computers. I'm still trying to figure out the cause of this.
At the moment, there are a few possible solutions to try:
1. Power down your computer, restart it, then re-run Atom Zombie Smasher.
2. If you have a joystick/gamepad, try plugging it in before starting the game.
3. If that does not work, go to your Atom Zombie Smasher's "data" folder (likely c:\program files (x86)\atom zombie smasher\data) and delete the ATIGTKXX.dll file.
4. If that does not work, go to your Atom Zombie Smasher's "data" folder (likely c:\program files (x86)\atom zombie smasher\data) and delete the OPENAL32.dll file.
5. If all that fails, copy & replace these libraries into your "atom zombie smasher\data" folder: http://blendogames.com/dev/sfml17lib.zip
Here's a rundown of all the cases described in this thread:http://blendogames.com/atomzombiesmasher/support.htm
If that doesn't help, let me know what your system specs are, specifically:
1. What OS you are using.
2. What video card you have.
3. Whether you're using a desktop, laptop, or netbook.