Open pafm.php with your code editor of choice,
then scroll down to the CONFIG section
(marked with '/*** CONFIG ***/').

Change these directives as you see fit.
The most important one to change is 'PASSWORD'.

Explantion of directives:

AUTHORIZE
	Require authorization (ask for a password)?

PASSWORD
	Password for authorization.

AllowPathInject
	Allow path injection? e.g. ../, /, etc.?

MaxUploadSize
	Max file size for uploading. In mega-bytes

MaxEditableSize
	Max file size for Editing. In mega-bytes

ROOT
	ROOT path of where you want to manage. Do NOT include the domain. Must be local