Scripting - Setting external editor

[Devalut]

As the title says, I accidentally set the editor to a broken program and now I don't know how to set it to a different one.

Editing preferences shows no source to editors,
and right clicking on scripts within CK simple says "OPEN IN EXTERNAL EDITOR" which opens the one I set it to that is broken.
Among other options that do not edit the target program.

Would gravely appreciate if someone could point me in the right direction.