Using fiddler to auto respond

Scenario:

We have got something working in Live but not in test environment after the release of new version, we were using the knockout framework on one of the SharePoint portal page. I had to check if the knockout different version is causing issue with our script. In order to quickly see if the same version which we got on live would work against Test environment. I did following

Using Fiddler:

1. Download Fiddler
2. Make a request to the portal Page
3. In fiddler session listing find the script file you like to replace
4. Right click on file and select decode Selected Session
5. On the AutoResponder Tab
  Enable the 'Enable Rules' checkbox
  Enable  the 'Unmatched Requests Pass through' check box

6.  Drag and drop the file to AutoResponder Rule Area
7.  At a bottom under Rule Editor section
Select the second drop down list and select the option of select a file
8. Select the file which you like fiddler to use to mimic response from server by using local file
9. Click Save
10. Refresh page