Ensure you have placed the files ipnstorez.php and pmstorez.php in your DragonflyCMS root directory.
Storez Pro makes use of a .htaccess file to ensure protection of your "Download Directory" - if you are on a Windows server without Apache, ensure you set permissions appropriately (subsequent notes assume an Apache server setup).
Warning: if you change from the default "Download Directory", you MUST add the .htaccess file provided in the distribution.
For product uploads make sure you CHMOD appropriately for your server for the paths specified in Storez Directory Settings, otherwise they simply don't upload (755 on some, 777 on others). Also set the file extensions you want to allow and maximum file size if your server allows greater than the default 2Mb.
With regard to image uploads, make sure you CHMOD appropriately for your server for the paths specified in Storez Directory Settings. Ensure your server is capable of using the image method you have selected in Storez Image Settings. Thumbnail size is adjustable.
There are numerous configuration options you can set to suit yourself. I won't go into them for now, so explore, and I'll add key aspects to this ReadMe as time progresses.
To run UPS shipping method, I gather you must have CURL running on your server, you need to register at http://www.ec.ups.com and you need to get an XML License/Developer key to use the method from this site. If this info is correct, it sounds very similar to what is required for Amazon services. Since I don't use or have access to UPS, the only help I can provide here will be from your feedback.