I didn't understand the preoccupation with
dmake, so I ignored that requirement... I already had MinGW and Microsoft's nmake installed, so I just downloaded and installed the new Activeperl 5.8.8.816, as my previous install was 5.8.7.813, slightly too old...
I ran a few test builds of XS modules (Sub::Name, Data::Dump::Streamer). Guess what: it works. You don't need dmake, nmake will do fine.
An exception is Win32::API, but we knew that already, it uses MSVC inline assembler syntax and MinGW's gcc can't handle that.