After upgrading Servercat, the application crashes upon opening. The user wants to revert to a previous version but cannot do so as they do not have access to a Windows device. They download PD and install Windows 11, then use PD Activator. They download iTunes on Windows and use an iOS app downloader tool to install the desired app through iTools. They recommend using Parallels Desktop 19 and advise logging into an Apple account on iTunes before intercepting the download.