For the sake of some closure, I have something unpretty that works:

use strict;
open OUTPUT, ">c:/temp/warning.txt";
my $mytime=(time);
my ($File,$FileStat,$CallOutDir);
chdir 'F:\Solimar_Work_Directories\XVTP\XVTP Cluster Feed' or die "Arg
+hh!!! $!";
opendir(ROOT, ".") or die "Arghh!!! $!";
foreach $File (readdir(ROOT)) {
    next if $File=~/^\./; 
    next if ($File eq "_Watched_Folder_._Active_");
    next if ($File=~/\._Checking_File_Readiness_$/);
    next if (-d $File);
        if ($FileStat = (stat $File)[9]){
        if ($FileStat <= ($mytime - 300)) {
        print "File older than 5min found. The file name is $File";
        print OUTPUT "File older than 5min found. The file name is $Fi
+le";
        last;
        }
    }
}
close OUTPUT;
[download]

I'm looking into adding some more functionality and flexibility to what's there. In the meantime it's doing what I need it to.