i had to spaghetti together a to xrni converter for my sf2 and exs files, it cannot convert every kind of exs and sf2 for sure, but if you’re desperately in need of another converter, give it a try
http://www.fileserve.com/file/gNCZTKp/toxrni.c
requirements: win32, mingw, 7zip exe installed, flac exe installed, patience