Just for further debugging:

This suggests that the Module::Build / Alien::Build concoction wants to run what it thinks is a shell script through the shell, except that there is none defined:

C:/berrybrew/5.26.2_64_PDL/perl/site/bin/ -c
[download]

There is a shell missing after bin/. Of course, cmd.exe is a shell, but it doesn't take a -c command. The snippet passed to that "shell" is clearly cmd.exe syntax, so something goes wrong somewhere there. I don't know where that snippet comes from, so it's hard for me to say. Maybe that snippet is the WxWidgets-supplied Makefile so you have to look into makefile.gcc to see where/how it sets up a shell and how/why that shell thinks it can run commands with a *sh syntax when the commands are cmd.exe syntax.

Update: Most likely, GNU make examines $ENV{SHELL} and if that is set to some weirdo value (or set at all), it will use that instead of falling back on cmd.exe. My advice is to unset $ENV{SHELL} and try again.