Emergency code editing
Iguana checks out the code that it is working on from fossil into a local “sandbox” directory (<Iguana-install-directory>/edit/<user name>/). In an emergency you can edit this code directly. For example if Iguana is crashing when you open a script, then you could edit it manually to resolve the issue.
See this explanation of the fossil repository layout for more information.
Continue: Running Iguana from the command line