Configure Sahi
The Sahi configurations are defined in the twist.properties file. You can configure sahi by "Editing Twist Properties"
GUI for editing Sahi properties is as below:

Sahi options on Twist properties file
The browser type and other configuration options can be defined in the twist.properties file.
The following Sahi options are supported in Twist:
- sahi.browserExecutable: This is used by Sahi to launch the browser. This points to the OS specific browser executable and is defaulted to standard location. In case of Windows 64-bit this needs to be changed from ...\Program Files\... to ...\Program Files (x86)\...
- sahi.browserOptions: These are browser options that Sahi uses while launching a browser. They vary from browser to browser.
- sahi.basePath: This is the path where Sahi exists. By default this is under where Twist is installed and should not be changed unless you know what you are doing.
For IE, Safari and Chrome, set the browser proxy to host: localhost and port: 9999