What is the difference between Standard and Enterprise licenses of the module?

Standard license allows only one installation of the module on one domain, one dnn portal or one dnn installation. Enterprise version allows multiple installations on multiple domains, portals or websites.

I got an older version of the module and would like to upgrade. How do I do that?

All updates within one line of the product are free. You need to access "downloads" section of your Snowcovered or Coding Staff modules store account.

URL image links open in a new window. Any way to simply go to a page on my site other than opening a new instance of my site? I don't mind using a URL to link to a page on my site, but don't want the new instance of a web browse

Please check module's settings, you can find this setting there.

Can I adjust the width and height of the display?

Yes, you can set width and height in module's settings.