Setting up the debugger requires two steps:
Install the PadWalker Perl module.
It is possible to use the debugger without installing PadWalker, but in this case local variables won't be shown.
Download the PadWalker module from CPAN (PadWalker 1.5) and install as described in the installation notes or use the installation manager provided with your Perl installation (e.g. PPM for ActiveState installations).
Earlier versions of EPIC provided a custom-compiled version of PadWalker for ActiveState 5.8.x. This is no longer necessary; you should simply use the most recent version of PadWalker distributed by ActiveState.