The tool itself is downloaded as a ZIP file. Inside, there is usually an executable. Some users mistakenly try to run the ZIP file or think the tool is for unzipping archives. It is strictly for converting game ISOs.
You will see a simple window with four main sections: psp iso compressor v1 4 zip
The application functions as a multi-format converter, primarily targeting the compression of files into CSO (Compressed ISO) and DAX formats. The tool itself is downloaded as a ZIP file