When I call GetCounterNames I get a:
Undefined subroutine &Win32::PerfLib::GetCounterNames called at xxx.pl line yy.
I use Win2k and perl, v5.6.0 built for MSWin32-x86-multi-thread (AP613).
Microsoft has probably changed some internal stuff that makes it uncompatible (in their usual care for peoples invested time and money :).

/brother t0mas