Turkey,
I have come across a very similar problem you have but my problem was a bit different when I update the ZA Free v6.0.631.003 to v6.0.667.000.
What happen was the normal uninstall ZA way didn't shut down ZA before updating, when I install the new version my ZA went crazy didn't work well.
The automatic ZA uninstall from the control panel section didn't shut down ZA properly, so I had to do it the old way and it works.
Follow my instruction.
1. Before updating the new version of ZA manual shut down ZA first, by dragging your mouse to the bottom right corner of your screen where the clock is located and you see a ZA icon. Left click over the ZA icon manual shut down ZA dead.
2. Then goto the control panel section to uninstall ZA, depending on what OS you have to uninstall the ZA software. It will ask you to reboot your PC, please reboot.
3. MS will popup a warning that you don't have your firewall enable or turn on, MS will automatically turn on the window firewall. You need to manual shut MS Window firewall and don't worry about the MS security popup message.
4. Goto to harddrive into program files directory right down bottom and manual delete ZA directory, and you don't really need to clean the ZA windows register.
5. Okay you can go ahead an install the new version of ZA.
My works like magic.