install r4 on Windows

Right-click the file you downloaded from Gumroad, choose “Extract All”, and open the extracted folder.
Open a second File Explorer window, and paste this into its address bar:
```
C:\Program Files\Common Files
```
Copy r4.clap into the CLAP folder there, r4.lv2 into LV2, and r4.vst3 into VST3, replacing any old copies. Create a folder if it is missing. Windows asks for administrator permission to change these folders.
When your DAW next scans for plugins, it should find r4.