I want to try to install a second version of a docker contianer from the Apps repository. But when you click on Actions it gives you the options for WebUI, Edit or Uninstall. What about installing again to a different appdata folder with different port/Ip settings?

You need to change the name of your current container first, then you can install the same container again. Or if that app has multiple authors, you can just choose a different author of the same app, so you don't need to rename your current container.