Building Mozilla or FireFox from source
 

Has anyone tried building Mozilla or Firefox from its open source?

I have, but then again if the source is available, that's what I'll build it from.

I've built it from source. It takes a bit of time as there is a lot of source there.... are you having prolems building it?

I am building it on a Windows computer.

Part of the process asks me to set something in the "path".
It has been a long time since I was asked to do that. It is a throw-back to the ol' DOS days and the ol' autoexec.bat

How do I do this with Windows XP?

There are many ways to do it., heres one:

Control Panel --> System --> Advanced --> Environment Variables

Under System Variables there is a entry that says PATH. Add your path preceeded by a semicolon to the end.