Allow install directory selection for desktop builds

Hello All,

Another recent bug thread mentioning games overwriting each other upon install reminded me of this feature request idea I had, which I never posted.

For desktop exports, I feel it would be very beneficial to have an additional option around whether the user can select the install directory or not. Right now the installer just defaults to auto-install, which can be problematic for both testing and pushing to platforms like Steam.

The manual way to toggle this in the export is only a few lines in the package.json file (included below), so having it in the UI rather than forcing users to modify their exported files seems like the next logical step.

The only requirements to enable this behavior is modifying the package.json file around line 13.

    "build": {
        "directories": {
            "buildResources": "buildResources"
        "nsis": {
            "oneClick": false,
            "allowToChangeInstallationDirectory": true