Please see https://github.com/SMerrony/EWItool2/wiki/Using-EWItool before installing and using this release. OS X users please note especially prerequisite number 4.
The jar file below should run on all modern versions of Windows, OS X and Linux providing that the prerequisites referred to above are met.
64-bit Windows users who do not already have Java installed could try the .msi installer file below which packages the required Java runtime with EWItool and installs it privately under your account in Windows without affecting other software or users.
Looks really promising to me. I hope this results in a nice stable editor for modern operating systems, and a vibrant community to share some awesome patches for the EWI 4000s.