The plugin is supplied in the zip file format, it has to be unzipped (unpacked/extracted) and the “widener.ny” file put into Audacity plugins file, same as you did with Anwida DX Reverb Light …
After you put an effect into the Audacity plugin folder, tick all the boxes here, then restart Audacity, (i.e. off then on again).
widener.txt (1.1 KB)
widener.ny (2.08 KB)