Did you research what it takes to make an application U3 compatible? Here's a summary of what it requires which was extracted from their "Ingegration Factors Worksheet" at https://www.u3.com/developers/downloads/reference.aspx https://www.u3.com/developers/downloads/reference.aspx
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1. Modify application to use the U3 runtime environment variables for all file path operations, licensing, and runtime action behaviors. The result of this activity will be an application that is insulated from the dynamic factors resulting from being supported on a removable mass storage device.
2. Implement U3 Action executables to customize runtime phase behavior: application installation and uninstall, runtime host configuration if required, application start, application stop, and runtime host cleanup if required. The U3 Launchpad doesn’t require a traditional installer application like InstallShield. The deviceInstall
3. Incorporate U3 Upgrade Process for appropriate activities: Activation, upgrade, etc…
4. Create Package contents: application manifest file, download manifest file, application icon file, U3 Software Central downlpage graphics, etc…
5. Complete U3 Smart Application Certification Self-Test and submit application for compliance verification |
Piece of cake right? Now, as far as making an app "portable" all you have to do is store your data files and configuration files in the same place as the application. ClamWin's installer attempts to use %APPDATA% and other places which are typically installed on the C: drive, which is why there is a separate portable version.