I wrote a quick scrip that basically is a copy and past of what you submitted:

use Win32::FileOp;

Map R => '\\\\Relmrx\\RELMRX', { persistent => 1 };
[download]

When I run this script I get the following:
Can't locate Win32/FileOp.pm in @INC (@INC contains: E:/Perl/lib E:/Perl/site/lib .) at mapdrive.pl line 4.
BEGIN failed--compilation aborted at mapdrive.pl line 4.

Where can I get the Win32 library?

5DXuser