No problem, in answer to your questions:
1. No you won't own the source code, but the purchase includes all the theme files which are not encrypted, so you are free to make modifications as you wish, including removing the footer credit.
2. The Photoshop .psd files are useful for web designers who may wish to redesign the layout of the theme. It makes things easier by containing all the color, height, width information relating to the template. Not having these files does not prevent you from making changes to the code though. And, if you purchase a standard license and later decide you need the files, you can always upgrade to developer later.
3. This is not a default feature of the theme, however there is a plugin available in the
AppThemes marketplace which includes LinkedIn integration amongst many other features, called
FXtender Pro, so you may like to check it out.
4. If your subscription expires and you choose not to renew it, you can continue to use the theme, however you will not have access to theme updates or support.
5. Theme purchases do not include installation, however we do provide
documentation to guide you through the process, and support is available in our forums. Thanks.