PHP Settings => Main Settings and use the combo box to choose which PHP version you want.
Applications made with ExeOutput for PHP 2019 and higher are really stand-alone: they do not require any additional components (the Microsoft Visual C++ Libraries required by PHP are built-in).
Windows 7 or higher is required. If you want your app to run on Windows XP or Vista, then download and install ExeOutput for PHP 2 to make Windows XP and Vista compatible PHP apps.
See also: Working with PHP