Thanks for contributing to our forum. First of all, once you have opted into the Global Shipping Program through your eBay account, you will need to generate a new token from within your Auctiva account to make the option to select the Global Shipping Program available when listing your items.
This can be done by mousing over the "My Account" tab within your account, selecting the "eBay" option under "Settings", clicking the "Get New Token" option and then proceeding as directed.
Then, when listing your items using this option, you can go ahead and specify your free domestic shipping the same way you would have otherwise - by selecting “Flat Rate Shipping” for Domestic and entering “0” in the “Cost” field next to your domestic shipping service or by selecting “Calculated Shipping” for Domestic and checking the “This shipping service is Free” box next to the service you have selected.
Assuming you would like to use eBay's Global Shipping Program to ship to all the international destinations that are supported by the program, all you would need to do for your international shipping is select the “Global Shipping Program” option above the “Ship To Locations” section and enter your package details (such as weight and dimensions) in the usual fields.
If you would like to offer offer different shipping methods to certain international destinations that would otherwise be covered by the Global Shipping Program, you can do so as long as the “Allow me to customize international shipping by country” option is enabled within your Global Shipping Program preferences on eBay.
Provided you have this setting enabled, any international shipping options you may add using the regular “Flat Rate Shipping” or “Calculated Shipping” area for International would automatically override the Global Shipping Program specifications for the destinations which select these alternate shipping options are available for.
If you have not done so already, I also recommend going through the following page of eBay's Help index for more details about the Global Shipping Program: http://pages.ebay.com/help/sel...ipping-globally.html
I hope this helps!