1. The sequence of ppm commands you've shown does not demonstrate that you actually installed Mail::Sender. Try Herkum's suggestion. Even when you got around to using its search in the CLI, you quit without following up.

2. You changed the shebang, but the use lines still have nix-ish paths. Are you sure that's right (and I ask despite seeing that @INC purportedly includes them)?

3. There are several excellent tutorials on installing modules here (though, TTBOMK, none that deal specifically with ppm4 if that's what you're using). See
  A guide to installing modules for Win32 and replies and references

      and
  A detailed How-To for locally installing modules