If KeyTweak messed up your Ctrl key and want to access the Task Manager, simply right click on the taskbar and select Task Manager.
Alternatively, you can remove the application from your PC without the need to even press the CTRL button. Simply press the Windows one and type Uninstall or go to Start > Control Panel > Uninstall a program. Locate KeyTweaks in the list and remove it, then restart the PC.