To push zones from dev to live, you create a file called snippets/sa-allow.liquid in the live theme of live.myshopify.com. Add the myshopify domain of any shop you would like to allow pushing from. In your case, it would be dev.myshopify.com.After this is done, you should be able to use the pushing dialog now. To bring up the dialog, go to the page to be pushed and select bulk actions > push sections to.Then enter the live myshopify domain live.myshopify.com in the destination shop text box. Choose the theme, zones, and placement. Last select which page(s) the zones should be sent to.