Default application path doesn't work

[eluser]tarsusc81[/eluser]
Duh. Wow, this was one of those times where, by the time I figured out where the problem actually was, I was too disoriented to think straight.

And by the way, the reason my controller class was failing was because I was extending my own MY_Controller class; in v1.7 that resided in /libraries, which is where I still had it, but in v2 it should reside in /core. So the file wasn't being found. I wonder why CodeIgniter wasn't made to throw an error when it can't find a class file in the autoload (and why PHP doesn't throw an error when I try to extend a class that doesn't exist).