What are the issues?
FWIW, one can download mingw32-openssl from fedora, thereby obtaining portable (across Win32) binaries without all the work.
I don't know what the issues are-- I do Mac/Linux these days (I don't do Windows). Does the precompiled fedora mingw32-openssl support ECSDA signatures? Can you give it a try and let us know if it works? (just add -DUSE_SSL to the Makefile and link with whatever libssl is called under mingw32)FWIW, one can download mingw32-openssl from fedora, thereby obtaining portable (across Win32) binaries without all the work.