FWIW, Re^2: Client/Server sockets with TK on Win32 doesn't work for me either under Tk or Tcl::pTk, but Tcl-pTk-0.85/t/fileevent.t does work (its a pipe open to perl program), but it i switch  use Tcl::pTk; with  use Tk; in Tcl-pTk-0.85/t/fileevent.t then it doesn't work

So problem with Tk.pm yes

Maybe socket problem with Tcl::pTk, or maybe with Tcl